To even not love it would put you in the super minority of American sports fans. The NFL is the best thing going, and 97%* of the sports watching public agrees.
Because they're told to. The NFL hype machine is like no other. The reality is that the typical regular NFL season game is a relatively meaningless and conservative slog that everyone involved treats like it's the Battle of Iwo Jima.
You asked earlier how someone could like college football but not the NFL. To me, that's a big part of it. I completely agree the quality of play on the field is better in the NFL. No doubt. But I'm not really watching to admire technical expertise. I'm watching for excitement.
The NFL has become so regimented that a lot of times it's frankly not very exciting. Run on first down. Punt on fourth. Throw it away if no one's open. Etc, etc.. And it's a sport where 8-8 teams can still win the Super Bowl, so it's hard to get that worked up about an upset in October.
Compare that with college football, where there are dozens of different approaches to the game, where a flawed but brilliant individual player (like Johnny Manziel or Everett Golson) can take over a game and make plays you never thought you'd see, where 19-year-olds will be 19-year-olds, sometimes rising to transcendence and sometimes shitting the bed entirely, making for all manner of upsets, and where those upsets matter because, for most teams, even with the playoff, losing one game knocks you out of the title hunt and losing two means you're playing just for pride (and a lot of teams that are just playing for pride do a lot of amazing things).
Throw in the pageantry and the rivalries and the tribalism and college football's just a lot more fun.
So I don't hate the NFL (though I do have serious problems with the way the sport is run). But I have two little kids and really only time to watch one. No question I choose to watch college.