It’s a more interesting question than you’re acknowledging. Think of the wedding at Cana. Christ’s first public miracle was turning water into wine: not at the beginning of the feast, but at the end, when the wine had run out…meaning people had already been drinking it. Not only did Christ fail to condemn the drinking of wine, He enabled people to drink more of it.
I’m not trying to be flippant here or paint Jesus as some kind of heavenly frat brother who just wants us all to get loaded whenever possible, but I do think it provides some direction on the basic question of “Should we sometimes eat, drink, and be merry?” Yes, because He did. St. Thomas Aquinas allowed that drinking “to the point of hilarity” was alright.
The idea that Christianity always and everywhere condemns even mild intoxication is, in my opinion, wrong. And I can see how someone could take that logic and apply it to the occasional, moderate use of marijuana. Now, maybe they’re wrong. But dismissing it as just Cheech and Chong looking for someone to help them rationalize their drug use is too easy, I think.
Again, I have no dog in this fight. I don’t smoke weed. But some of the condemnations here are just overwrought. There are many people who use weed on occasion and live healthy, productive, normal lives. (And yes, there are many people who abuse it and fry their brains.)
As a final note, talking about “drugs” in a conversation like this is way too broad to be helpful. As people have noted, weed is a drug. Heroin is a drug. Aspirin is a drug. Antihistamines are drugs. We need to look at them individually.