Not true. All airports don't have scanners and if you set off the metal detector, for any reason, you're going to get groped.
That hasn't been my experience. Generally you get a second (and sometimes a third, or fourth, or...) try through the metal detector, and if you still can't figure out what's setting it off they break out the little metal-detecting wand. If THAT is still picking up something, and they can't tell what it is, you get invited to the little room.