Well, I actually used to be a competitive curler, so my view may be biased. :hammer:
My views of what is a sport and what isn't is pretty narrow though. Nascar, horse racing, dancing, hunting, etc are not sports to me. :nutkick:
I think of curling as more of a game as opposed to a sport per se. (But I did get an athletic scholarship based me curling...) But also in that regards, I'm hesitant to call baseball and football a sport too to be honest - they're games.
But...when compared to what is considered Olympic events, curling does deserve to be in there. The least important thing in curling is the sweeping. It's all in the strategy and delivery of the rock. It's quite very challenging. (The average person would have much more difficulty in accurately throwing a rock than they would a football).
But I shall list a few other Olympic events that would have to be removed if curling was:
1. Equestrian - c'mon, the horse does all the work
2. Shooting range stuff - are you serious?
3. Archery stuff
4. Events that a score can not be qualified with accuracy (such as dancing, diving, synchro swimming, etc)
5. Bobsled and luge. You push then hold on???
6. Baseball
etc...
On the note of football, although I'm not a fan of it, I would initially think it should be considered to be in the Olympics too (baseball and hockey are). BUT - what you're talking about is "American football". Do other countries even play this sport? Canada plays a very similar game, with some "minor" rule changes. But I don't imagine there would be enough countries that would have a team to represent - I think rugby is much more popular worldwide.
I'm sure the 2 main factors in choosing events are:
1. Enough worldwide acceptance and competitors
2. Can we generate money from this?