You need bodies in practice. You need your two deep to be working on themselves and game prep, not learning and running other team's plays for practice. If you limit your roster to 13 scholarship players, you don't have a full team to learn and run the opponent's plays for practice. You need about 5 walk-ons for that purpose. If you want to be able to run two stations of 5 on 5, you need 7 walk ons - and that's without anyone being held out of a practice for injuries or rest. Football scholarship provides 3 deep on scholarship, plus another 19. Basketball allows approx. 2 1/2 deep. So, walkons are probably more important for practice depth than in football, IMO. Yes, you spend resources on the walk-ons. But, if you don't give them access to training table and a few perks, see how many you get willing to do it. Its a grind for those kids with little to no other reward.