I think a lot of what people hate about the scans is low-level radiation, and the fact that if you opt-out you get basically felt up...the whole thing feels like an invasion of privacy either way. You either get to be mostly undressed in a pixal-y image and possible cancer risk, or have to be touched 'intimately' by a TSA worker (granted, its someone of your gender, but what difference does that make? D: )