It's been a while since I've done any sort of photography in public, other than events where cameras are expected (vacation spots, Ozzfest, etc.), because of this: photography in public is a suspicious thing. People want to know why you'd want a picture, and figure you're up to no good, and if you were up to no good, you wouldn't tell the truth if they asked anyway. Because, you know, a photographer with a conspicuous high-end camera is trying to be sneaky.