You are 100x more likely to get ripped off on the street. Why would a business take took effort to build up a rep and a flow of cash risk it so they could rip off a few get bad reviews and lose it all.
Once you find a dealer who buys 500/1000 dollars worth (to make that 100% markup) they don't stand on a corner because those people get robbed / arrested. But they expect customers to buy larger amounts.
Though here at least, with dispenseries and legalization, that's all changed.