Um teams already have a salary cap. Even though they don't it shouldn't be up to the league to determine a cap for all teams anyways. The owners of the teams don't grow money on trees. They negotiate with the players and not all players look for bank. Some players are loyal to their squad. Look at Jerry Rice. He didn't leave the 49ers, they let him go. Then he went to oakland, then denver, then back to san fran to retire where he started. In a one day contract he made $1,985,806.49 and retired. 1985(drafted), 80(his #), 06(retired), 49(49ers).