Well, yeah, the tourists are the ones who end up in bad situations, but to some extent the smart shop employees are to blame as well. I've heard a few of them telling young travellers (as in 16 year olds!) to just take mushrooms and go to a coffee shop and smoke a large joint while waiting for the mushrooms to kick in. That's incredibly bad advice for a first time shroomer.
I have to agree with you on this one. I was in Amsterdam recently and there are multiple shops that have hand-made "dosage posters" saying:
Beginner = 10 Grams
Intermediate = 15 Grams
Expert = 20+ Grams
I understand that these are truffles, so it takes more weight to trip, but they (both the posters and the shopkeepers) are very misleading. Don't get me wrong, I've tripped many times on a bunch of different substances and had many great times. But I took around 15 grams one night and was pretty floored. I ended up having a great time, but I can't imagine what would happen to a naive person who thought "If they're legal, they must be safe right!?!?!!" and ends up biting off way more than they can chew.
It's not necessarily all the tourists fault when powerful substances are being peddled to them purely for profit. The shops don't really care what the result of someone taking their mushrooms is as long as the person can pay for them.

