Wow, it's great to see that some people actually wave and enjoy doing it. We too will keep waving; someone's bound to wave back at some point, right? :C
I see some of the same kind of replies and comments on the motorcycle forums about waving... "what for", "why bother", "I'd be waving every second and not enjoying the ride", and there's nothing wrong with that either.
Everyone's different, some wave, some don't, no skin off anyone's back. I think it hurts not a thing if done safely and may actually make someone laugh or smile. We all share something in common and have some of the same challenges on the road, and isn't this hobby or lifestyle of ours about having fun?
Just my .02.