Not really if you think about it for a moment: Your legally a man at the age of 18... Are there any players in the NFL younger than 18? Not-a-one.
They are no kids in the NFL. Only men and punks... Wish the NFL would do something about the latter few.
Legal for some things at 18, not legal for others.
My point is simply that professional sports are kid's games. That we let a tiny percentage of the overall number of players continue to play professionally is, IMHO, the exception that proves the rule.