Some Prius drivers definitely can be self righteous types. Around here most people buy them for the image (you'll see one parked next to a Hummer in the driveway of a multi-million dollar home) but others think they are saving the world. If they slow you down you'll consume less gas and release fewer harmful emissions
.
But in reality we just consume and release more as we drop to 3rd and fly on by at WOT.
I do encounter a lot that speed like mad.