The issue is that with alcohol you can feel yourself getting drunk, and most people can choose to stop before they have too much. It's a choice thing to drink more, and if you do something stupid because you're drunk then it's your responsibility because you should've stopped drinking before losing control.
Other drugs aren't quite so easy to control, once consumed that's it, you're on that trip whether you like it or not. That's why they are more dangerous.
And I wonder why that is?
I'm not a mushroom expert but I'm guessing that some are stronger than others, and taking more of the mushroom (certain amounts) would strengthen the effects.
Just like the difference between vodka and beer, and how do we know that there is a difference? Because there is labels on the back telling us the alcoholic percentage.
Alcohol is moderated, and if mushrooms were moderated too people wouldn't go over the top like they do with Alcohol.
However I don't know how shrooms work and maybe a little bit is just as bad as a lot of mushrooms (don't see how that would work though.
So comparing those two is pointless and using that you know you're getting drunk is pointless too and a bad comparison.
Because you know how much you're consuming when taking alcohol because the government makes sure you KNOW how much you're taking.
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Also people when taking drugs or shrooms usually take one hit and they're gone. However with alcohol it's different because you take smaller quantities of alcohol and progressively build up the drunkenness. If there was a universal shot that instantly got people to 'being drunk' then you would have lots of people who, get drunk, don't get drunk, and for some it would be too much just like with people taking a mushroom.
Fact is people saying if drugs were legal people would abuse it. Well people abuse everything and that's life. If the government moderates things and does as much public campaigning on drink safe etc as it would on other drugs then people (the majority of the time) would be safe on things like mushrooms.