Yeah I can't believe the NFL is like a 15? 17? game season. Including playoffs. You've got 38 matches in domestic leagues here (or round about 30-40), probably 5-6 on average in the cup (depending on how far you go and if you have two competitions like England, France, and Portugal. and if there's replays. You could probably play 15 cup matches in England.), and then whatever amount in Europe, which for finalists is 13 I think if you start in the group stage. There's more rounds in the Europa League anyway.
So yeah, they might dive, but you have to be in damn good shape to be a footballer. Oh, not to mention that's an hour and a half of running, potentially more in knockout competitions.
Wow, I haven't even mentioned international tournaments, qualification, and friendlies.