heres my thing, I wave when I get a chance or I think of it.
SOOO many people get heated over this topic! Its rediculious!
I am still a new rider, my first wave I actually remember LOL. But being a newer rider I am focusing more on my skills then I am to pleasing anyone else. So if I dont wave, cry me a river or I'll meet ya at the diner someday and we can chat about bikes. I read an article a few months ago about waving and it made alot of sense. Pretty much it boiled down a ride in germany or europe somewhere & a guy at a place complaining that no one waved back. Someone stepped into the convo overhearing it & explained that it was because there are so many riders out there that they concentrate on the ride & make friends at the next stop.
IF I NOTICE that someone waved, I will try to wave back. If I cant meh oh well. Now the only time I would give a finger or want to get the middle one, is if its from A friend or if my friend doesnt wave at me. If I am on a part of a ride where I am relatively safe (IE: highway, no cars very close around me) then yeah I'll wave if I see a bike standing out.
Here's another one ;) I get ripped a new one for this all the time but I dont care. I dont wave to scooters. Its not the same thing. Its no disrespect, its just that it is a different culture. The biker wave use to mean "Hey man! Nice to see another! If something happens I got your back" now its more like "HAAAAAAY HAAAAAY!! Look at me!!! I got a bike too!!!"
So the scooter thing? Different culture - same risks just in town (most of the time). I dont hate scooters or scooter riders, some wear gear, some race scooters, some do long distance trips, I dont mind scooters. Its just not in my head to wave to them.