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                          OFFER TO PURCHASE FOR CASH
                    ALL OUTSTANDING SHARES OF COMMON STOCK
 
                                      OF
 
                            DART GROUP CORPORATION
                                      AT
                             $160.00 NET PER SHARE
 
                                      BY
 
                             DGC ACQUISITION, INC.
                      A DIRECT WHOLLY-OWNED SUBSIDIARY OF
 
                            RICHFOOD HOLDINGS, INC.
 
 
    THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK
      CITY TIME, ON TUESDAY, MAY 12, 1998, UNLESS THE OFFER IS EXTENDED.
 
 
                                                                 April 15, 1998
 
To Our Clients:
 
  Enclosed for your consideration are the Offer to Purchase, dated April 15,
1998 (the "Offer to Purchase"), and the related Letter of Transmittal (which,
together with the Offer to Purchase and any amendments or supplements thereto,
collectively constitute the "Offer") relating to the offer by DGC Acquisition,
Inc., a Delaware corporation ("Purchaser") and a direct wholly-owned
subsidiary of Richfood Holdings, Inc., a Virginia corporation ("Parent"), to
purchase all of the outstanding shares of common stock, $1.00 par value per
share (the "Shares"), of Dart Group Corporation, a Delaware corporation (the
"Company"), at a purchase price of $160.00 per Share, net to the seller in
cash, upon the terms and subject to the conditions set forth in the Offer.
Holders of Shares whose certificates for such Shares are not immediately
available or who cannot deliver their certificates and all other required
documents to First Union National Bank (the "Depositary") or complete the
procedures for book-entry transfer prior to the Expiration Date (as defined in
the Offer to Purchase) must tender their Shares according to the guaranteed
delivery procedures set forth in Section 3 of the Offer to Purchase.
 
  WE ARE (OR OUR NOMINEE IS) THE HOLDER OF RECORD OF SHARES HELD BY US FOR
YOUR ACCOUNT. A TENDER OF SUCH SHARES CAN BE MADE ONLY BY US AS THE HOLDER OF
RECORD AND PURSUANT TO YOUR INSTRUCTIONS. THE LETTER OF TRANSMITTAL IS
FURNISHED TO YOU FOR YOUR INFORMATION ONLY AND CANNOT BE USED BY YOU TO TENDER
SHARES HELD BY US FOR YOUR ACCOUNT.
 
  Accordingly, we request instruction as to whether you wish to have us
tender, on your behalf, any or all Shares held by us for your account pursuant
to the terms and conditions set forth in the Offer.
 
  Please note the following:
 
    1. The tender price is $160.00 per Share, net to the seller in cash.
 
    2. The Offer is subject to there being validly tendered and not properly
  withdrawn prior to the Expiration Date a majority of the outstanding Shares
  (on a fully diluted basis) and certain other conditions. See the
  Introduction and Sections 1, 14 and 15 of the Offer to Purchase.
 
    3. The Offer is being made for all of the outstanding Shares.
 
    4. Tendering stockholders will not be obligated to pay brokerage fees or
  commissions or, except as otherwise provided in Instruction 6 of the Letter
  of Transmittal, transfer taxes on the purchase of Shares by Purchaser
  pursuant to the Offer. However, backup federal income tax withholding at a
  rate of 31% may be required, unless an exemption applies or unless the
  required taxpayer identification information is provided. See Instruction
  10 of the Letter of Transmittal.
 
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    5. The Offer and withdrawal rights will expire at 12:00 midnight, New
  York City time, on Tuesday, May 12, 1998, unless the Offer is extended.
 
    6. THE BOARD OF DIRECTORS OF THE COMPANY HAS UNANIMOUSLY DETERMINED THAT
  THE OFFER AND THE MERGER (AS DEFINED IN THE OFFER TO PURCHASE) ARE FAIR TO,
  AND IN THE BEST INTERESTS OF, THE COMPANY AND ITS STOCKHOLDERS; HAS
  APPROVED THE MERGER AGREEMENT (AS DEFINED IN THE OFFER TO PURCHASE), AND
  THE TRANSACTIONS CONTEMPLATED BY THE MERGER AGREEMENT, INCLUDING THE OFFER
  AND THE MERGER; AND RECOMMENDS THAT THE COMPANY'S STOCKHOLDERS ACCEPT THE
  OFFER AND TENDER ALL OF THEIR SHARES PURSUANT THERETO.
 
    7. Notwithstanding any other provision of the Offer, payment for Shares
  accepted for payment pursuant to the Offer will in all cases be made only
  after timely receipt by the Depositary of (i) certificates for (or a timely
  Book-Entry Confirmation (as defined in Section 3 of the Offer to Purchase)
  with respect to) such Shares, (ii) the Letter of Transmittal (or a manually
  signed facsimile thereof), properly completed and duly executed with any
  required signature guarantees or an Agent's Message (as defined in the
  Offer to Purchase) in connection with a book-entry transfer, and (iii) any
  other documents required by the Letter of Transmittal. Accordingly, payment
  to all tendering stockholders may not be made at the same time depending
  upon when certificates for Shares or Book-Entry Confirmation with respect
  to Shares are actually received by the Depositary.
 
  If you wish to have us tender any or all of the Shares held by us for your
account, please so instruct us by completing, executing, detaching and
returning to us the instruction form set forth below. If you authorize the
tender of your Shares, all such Shares will be tendered unless otherwise
specified below. An envelope to return your instructions to us is enclosed
herewith. Your instructions should be forwarded to us in ample time to permit
us to submit a tender on your behalf prior to the expiration of the Offer.
 
  The Offer is not being made to (nor will tenders be accepted from or on
behalf of) holders of Shares residing in any jurisdiction in which the making
of the Offer or the acceptance thereof would not be in compliance with the
securities, blue sky or other laws of such jurisdiction. However, Purchaser
may, in its discretion, take such action as it may deem necessary to make the
Offer to holders of Shares in such jurisdiction.
 
  In any jurisdiction where the securities, blue sky or other laws require the
Offer to be made by a licensed broker or dealer, the Offer will be deemed to
be made on behalf of Purchaser by one or more registered brokers or dealers
that are licensed under the laws of such jurisdiction.
 
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              INSTRUCTIONS WITH RESPECT TO THE OFFER TO PURCHASE
                FOR CASH ALL OUTSTANDING SHARES OF COMMON STOCK
                                      OF
                            DART GROUP CORPORATION
 
  The undersigned acknowledge(s) receipt of your letter, the enclosed Offer to
Purchase, dated April 15, 1998, and the related Letter of Transmittal (which,
together with the Offer to Purchase and any amendments or supplements thereto,
collectively constitute the "Offer") in connection with the offer by DGC
Acquisition, Inc., a Delaware corporation ("Purchaser") and a direct wholly-
owned subsidiary of Richfood Holdings, Inc., a Virginia corporation
("Parent"), to purchase all outstanding shares of common stock, par value
$1.00 per share ("Shares"), of Dart Group Corporation, a Delaware corporation.
 
  This will instruct you to tender to Purchaser the number of Shares indicated
below (or if no number is indicated below, all Shares) which are held by you
for the account of the undersigned, upon the terms and subject to the
conditions set forth in the Offer.
 
                       NUMBER OF SHARES TO BE TENDERED*
 
                                         SHARES
 
Dated:           , 1998
 
                                   SIGN HERE
 
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                                 Signature(s)
 
                     -------------------------------------
 
                     -------------------------------------
                                 Print Name(s)
 
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                     -------------------------------------
                               Print Address(es)
 
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                       Area Code and Telephone Number(s)
 
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                      Tax ID or Social Security Number(s)
 
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   * Unless otherwise indicated, it will be assumed that all Shares held by us
     for your account are to be tendered.
 
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