Coaches get territorial, football is definitely guilty of it. I always liked to encourage kids to do sports where they are exposed to many more teams and levels of ability like track or wrestling. A football schedule can mask how good or bad an individual actually is. If you play DB on a state championship football team, but run a 12.00, maybe you aren't as good as you think. If you play LB, but can't make the state tournament in wrestling, maybe you aren't as good as you think.
And I love that Alex Collins video. As funny as it is watching him play, I guarantee you he is giving effort and thoroughly exhausted after a game/practice. You can't say the same for a guy that's spent 6 months doing the same set of cone drills with loud grunting and foot dragging. Game speed is different, the sport doesn't matter.