Maybe here in the US, but there are many of them in Europe. They are very organized and have regular meetings and newsletters. A friend of mine is the president of the one at Vienna Airport in Austria.
Richard, I didn't know about WAS in DC. I don't think I'll join that club although sounds interesting but you have to pay a $20 annual membership. I suppose most of them are free? However, a local photographer in the DC area created a Baltimore/Washington spotter club and however I'm a member because it's free.
In Denver during the 80s there used to be a restaurant outside the fence of Stapelton Airport. I was a little kid then and I loved eating breakfast and watching planes land, and If the restraunt hadn't burned down and Denver International hadn't been built, it would still be my favorite place. Wish the new DEN had something similar, or at least a spotting area.
SNA Orange County and Phoenix Skyharbor also have very good spotting areas---the top decks of parking garages.