I live in a very kid-friendly, upper-middle-class neighborhood in Brooklyn. I'm always struck on garbage day how many perfectly good things are out on the street, especially kids stuff. Now, I know that it's illegal to re-sell carseats, but when I see kids toys and books out there I wonder what the hell is going on. In a time when nothing non-organic passes the lips of kids, where recycling is almost religion, why aren't we re-using more? Why aren't we passing things on to our friends, family or goodwill? Why are we throwing more plastic crap into the land-fill?
When i was a kid all the toys and clothes made the rounds of the neighborhood. You had to watch as your out-grown favorite party dress was handed off to your neighbor down the road. (And god-forbid you had a tantrum about it, because then you'd never get another one) Toys were yours, but you were expected to share.
I'm not a parent yet, but I think we hold some responsibility here. I think your child isn't going to appreciate something really nice if they get is always the best. They are going to think they deserve it, and not understand that there are some things you have to work for. As a parent, you shouldn't feel guilty about giving your kids second-hand stuff, you should feel proud that you're doing the right thing ecologically and ethically. That you are helping to create a person who values things and isn't part of the throw-away culture.