Timmy: Is it against Da Rules?
Cosmo: Well, no but…
Timmy: Then do it.
Jorgen: How many Timmy clauses do I have to add to this?!

The really fucked up thing is how broad this wish is.

He didn't just wish for everyone in the immediate area to be addicted to crack, or even everyone he knows. Just… everyone. On the planet. All instantly addicted to crack at the same time.

Drug lords would rise to power almost instantly, like full-on Mad Max warlords, providing the starving masses with the poison they now need to function at all.

And there's no time limit, either. So, presumably, every human born in the future would ALSO be addicted to crack. So, all the maternity wards on the planet would instantly be filled with screaming crack babies.

In seven words, Timmy almost certainly destroyed all organized society, and doomed the world to a new dark age. The fucking Joker WISHES he was Timmy.