Yeah, I don't think StackOverflow is your problem. I mean, if they're going to blindly paste code, surely doing that from community-curated examples is better than whatever junk they'd find.
It reminds me of the 'wikipedia can be wrong!' crowd - yes, that's inherant to the format. Yes, you are going to need to check things you read there, yes, your 20 page essay about why you are the best person in the world is going to get deleted.
Every time I see a critisism of SO, I tend to see someone who would make the site worse or is misusing the site. Not saying SO is perfect - more can be done to help those people become good contributors or users, but SO is very well designed, and the quality of the content is really very good.