Running plays rarely work in flag football. So there is no point to line up with a running back. As soon as you lineup with a running back, teams will know and key in on the running action and not bother covering the pass. With so few players in flag football, especially 7 on 7, putting a man in the backfield is wasting a player and allowing one more LB to rush in and not worry about a pass play.
This is your basic sweep play. Insted of pitching the bal to the RB to run the sweep, the QB just keeps it and runs it himself. Downfield blocking is crucial by the WRs. You have to block well.
This play can produce a lot of yards and is the play most flag football teams use.