Is the requester required to give a reason for a request?

No. FOIA requests can be made for any reason whatsoever. Because the purpose for which records are sought has no bearing upon the merits of the request, FOIA requestors do not have to explain or justify their requests.

The requester's reason for making a FOIA request may, however, be considered in the context of certain procedural decisions made during the course of processing a request; this is the case, for example, when the agency is deciding whether to grant expedited processing, or to waive fees, or when a court is deciding whether to award attorney fees and costs to a successful FOIA plaintiff.