Some are, not many
That's far too thin a reed on which to hang the complete illegality of recreational marijuana versus the general legality of recreational (i.e., non-medical) alcohol.
And note that when alcohol was illegal, very few used that drug for any reason other than getting drunk.
And with each drug, there are degrees of effect; someone using marijuana to get a little high may be no more affected than someone having two beers to 'relax'.
No response?
Well, since you disagree with most of my arguments so far, I can't help you here. I fundamentally reject the argument you make and the comparisons. I'll reiterate again: the purpose of every rec m/j users is to get high, it's that simple. That is not the goal of every user of alcohol.
"And note that when alcohol was illegal, very few used that drug for any reason other than getting drunk."
If that point is 100% true, then the reasoning behind enacting Prohibition was entirely sound.
"No response?"
I did reply. I reiterated my point above in this very post.