At least in my area I do not have an impression that scout kids are from richer families than all school kids (which should be a pretty good reference point; a little lower maybe because some of the richer parents take their kids to private schools).

I do see scouts take lots of active outside trips which can help with mental balance. Doing white water rafting, being thrown overboard, fighting elements, being cold and wet, seeing occasional physical injuries and the beauty of the stars in a desert can put minor life disappointments into perspective for a long long time. My 2c.