OK, come on, you don’t know that. I doubt we have any serious data that bodily fluids in public bathrooms are likely to come from drug users. And if you’re cleaning it up, presumably you have equipment and are not using your tongue, the residual drugs won’t jump on you. Don’t stigmatise hard drug users, many of them (maybe most) were given a rotten hand early on and now want help. Policies such as Portugal’s decriminalisation have shown we can make a bigger difference when we treat those people as people.
Either way, the point of your parent comment is that most people don’t even pick up trash, which is itself a problem.
I do know that. For a time I was GM for a convenience store. I started requiring people to come ask me or the manager on duty for a key to the bathroom, which I started having locked by default.
There was an immediate 90% reduction in bodily fluids outside the toilet bowl and 100% reduction in stolen plumbing (they were taking part of the p-trap for drug use) and in finding discarded paraphernalia. Correlation isn't causation, maybe all the crack heads were still using the bathroom but decided to be civilized, IDK, but keeping the bathroom under literal lock and key was a big benefit.
It was inconvenient for customers, that was true, and I didn't like that aspect, but it was hard getting staff (or even myself) that had the will to hose poop off a bathroom wall.
Which I can tell from your comment you've never done. "presumably you have equipment" Yeah, a hose. A mop and bucket. You're still in close proximity, you still step in it, it still splashes. And nothing prepares you for the smells. And you can never unsee it. I won't even describe the things I saw in the womens bathroom. Way less common for things to go down in there, but when it did... It's wretched work.
Cleaning up bodily fluids, which likely come from drug users, is a whole other thing.