When someone asks me if I watch a particular sitcom and I respond that "No, I don't really watch TV", it's purely for practical reasons. The times when I just say "no" with no explaination, it inevitably leads to a hundred further conversations down the road asking me if I watch this or that other show, and I have to say "no" again every time it comes up. Why not just nip that topic in the bud when it comes up the first time? I think it's more polite to just tell the truth, and not feel the need to imply "no, I watch a lot of shows but just not that particular one."
If you're not an opera fan and someone asks you if you've seen the latest production of Don Giovanni at some opera house, are you going to say you don't get to the opera house very much 'cause your not the biggest opera fan, or are you going to be all like "Aw, no, I didn't catch that one!" They're both "true", but I ask you, what's the bigger asshole move - being honest or pretending you're into something you're not into?
I think the people out there who throw around the "snob" word so easily when it comes to TV might just be a teensy bit defensive about their own viewing habits. I put them in the same class as those people who get irrationally annoyed at vegetarians/vegans. Same difference - sure there are assholes who brag about it or are condescending about it, but don't jump the gun and paint us all with such a broad brush!
Now if you'll excuse me, I have to get back to my yurt behind the Lady Foot Locker.