Fun fact: in some countries it's illegal for citizens to take illegal drugs even if they're abroad in a place where it's legal. E.g. if a Korean smokes weed during a visit to Amsterdam, they can be prosecuted for it upon return to Korea.
Isn't that pretty common? As a Norwegian, there's AFAIK several things I can't do when abroad even if it is legal in the country I visit. Doing drugs is one of those things, I believe.