Watching sports is a useful activity when you confined to a hospital bed for a month or two as has happened to people I know. In one case they wouldn't be allowed to game, even sports were in danger of being too exciting for their condition.
Logic does not check out. Like they're both activities I can do on my couch? Okay sure, I guess. Just like I can watch a video about knitting even if I can't knit, but I could be knitting instead of watching!? Complete nonsense...
I can only watch so much football as can a rare other people like me. If I am watching football I want the view of one position. I don't care that the quarterback got sacked on the play, how did the running back avoid the defense in his attempts to become open for a pass - or some such that I want to emulate when I next play. (i think that is a likely thing - I consider football too dangerous to play so I'm guessing - in reality I'd prefer to see other sports that I'm likely to play)
The game most of the world calls "football" is called "soccer" in the US. We have a very popular game we call "football" in the US that is unrelated to "soccer", instead it is related to rugby (still very different from rugby, but there is a relation)