Almost all of the dudes I've know who sell drugs never thought of it as a way to "level" up. It was a way of making money where there were absolutely no jobs. And most of them didn't make much above minimum wage. Several of them had minimum wage jobs on the side.

If you haven't already, you should watch The Wire (HBO) about how futile street busts are in either combatting the drug trade or improving the lives of people living in the city.