I didn't consider myself an environmentalist until recently, mostly because I thought everyone did what my family did!
I was brought up on learning to separate recyclables out of trash, and to turn the TV off if you aren't watching, or turn off lights if you aren't there, and to use reusable grocery bags and take public transportation/ride bikes/walk if it was feasible. I thought it was common sense.
Apparently, not everyone does these things. That said, I don't necessarily go completely out of my way to be green. I don't recycle peanut butter jars because they're too insanely difficult to get completely cleaned out.