Us canadians must be too nice -- pretty much everyone waves... sport bikes, cafe racers, harleys, even BWMs... crazy. If someone waves and I cant wave back I try to at least nod. That being said, I don't need a box of tissues if someone doesnt wave...
My parents live in a small town on the east coast and EVERYONE (not just bikes) waves at EVERYONE (walking, driving, sitting, etc, even if they don't know you). Being a big city boy it totally freaks me out.