You don’t think there are scholarships for baseball and hockey players?
Unlike pro football you don’t need to go to college to play major league baseball or hockey. Has there been a recent player who went straight from high school to the NFL? There are alternatives in baseball and hockey, but not football.
I have a theory about this. Professional football and basketball never developed minor league systems because the collegiate versions of these sports were actually more popular than the professional leagues up until around the 1940s. Baseball and hockey, on the other hand, already had extensive networks of minor and semi-pro leagues in place long before then.
They have bowling scholarships.
I have yet to figure out why.