i can understand handing over money to a friend before you get the weed, but to give a complete stranger 50 bucks without any weed up front is madness mate. It's one of those live and learn moments buddy, you wont do it again
You stereotyped him as a smoker/dealer. He stereotyped you as a sucker. Pretty cheap lesson to learn.
Why are you surprised? Hahahahaha "gives dude money, dude walks away. Dude where's the bud? You already gave me the money you don't get shit. Noob." Hahaha funny shit.