NBC is making concessions to the Canadian audience. For example, they showed curling in prime time the other night. Probably 0.001% of Americans can even describe the sport of curling let alone tell you the rules, strategy, skills and objectives involved in the sport.
I doubt it. I don't know ANY Canadians who watch NBC for their Olympic coverage. Every single Curling match involving Canada is shown on a Canadian network. Heck, they often show matches that don't even involve Canada.
Curling is very popular in some northern/midwest states such as Minnesota. I've been to bonspiels (a curling tournament) in Michigan, North Dakota & Wisconsin. I know some people who've played in bonspiels held in the state of New York.
As for what is being used to play the game, they're called 'stones'. They're quite heavy & you need a certain degree of strenght & skill to throw them. You also need to put a spin on the stones as you release them, in order to make them 'curl' as they're being thrown down the ice. The reason the two sweepers (sometimes three once it enters the 'house') are sweeping in front of each stone being thrown is to create some friction in order to make the stone curl even more.
The sport is extremely strategical & i can assure you that you'd be quite sore after just one match. It's no wonder that the players are more & more fit at the competitive level. For example, Canadian skip Cheryl Bernard is a fitness freak & probably is in better shape than half of the athletes at the Olympics. Have you ever seen a fat & out of shape curler at the national & international level? Rarely.
Attending a bonspiel is a hell of a lot of fun. Just take a look at the crowds at the curling matches & you'll see what a great time they're having. As a matter-of-fact, if i'd be attending the Olympics, two of the events i'd want to desperately attend would be Curling & Hockey.
For those interested to learn more about Curling, check the link below. It explains quite a bit & will likely make you more interested in the game the next time you want to watch it:
Curling explained
USA Curling