A good friend of mine played feetball for Virginia Tech and they all did squats and power cleans regularly. Feetball players need powerful legs. You get powerful legs from those lifts. It was a part of their official off-season S&C program. Again, they aren't doing it like they are training for a powerlifting meet. They incorporate it into their entire program in a way that makes sense. Squats and deadlifts are the meat and potatoes of any good S&C program. You don't often see them doing them on pictures and articles because it's boring. They want photos of them doing all sorts of crazy exercises, but that's not where they make their real gains. Any healthy pro athlete who trains in S&C is going to squat and deadlift or do some basic variation of it. It's a fundamental movement. For all of the sports other than feetball I listed, I have personally seen offseason S&C packets from various teams that list squats and such. The one program that surprised me was the offseason Seahawks defensive lineman program, which only squats 2x week for like 3 sets of 6/4/2. They also did powercleans for several sets of doubles. I'm sure by now it's different, but I got a hold of that packet when I worked for a high end S&C gym through one of my trainers who worked with the team.