Why is it that in Amsterdam you have coffee-shops where you can sit relax and smoke cannabis but nothing like that seems to exist in New York City? Or elsewhere in America, is there?
Honestly, it's probably mostly just a tourism thing at this point. Most of the Dutch people I know tend to not care about weed but they see coffee-shops as a thing for tourists or international students. If you're a regular user in NL, then you have a hookup or grow your own plants.
Also, anecdotally, I can smell a lot less weed in Amsterdam than when I've caught a wiff of it in the US. You have to be walking right by the shop before you smell it usually. I'm not sure if this is a local regulation or what, but I suspect the Dutch would be much less tolerant if their public spaces reeked 24/7 (but no worried about the dog poop on the sidewalk)!