Mental healthcare costs would easily eat the entire existing healthcare budget - so you're effectively looking at doubling the health budget to actually do it right. That's not cheap. It's also a largely humanitarian spend, as these people are unlikely to ever be able to repay the costs spent on them in their own taxes.

rolls eyes

Have you spent even five minutes considering the cost of not treating these people?

Here is one back-of-envelope calculation that always stuck with me: A street-dwelling heroin addict has, conservatively, $20k in expenses per year, mostly heroin. Inevitably, they will need to turn to theft for this money, since their chances of finding work compatible with their lifestyle is slim to none.

Stolen merchandise will generally sell for about 1/10th of its store value (very roughly). So in order to feed their lifestyle, this addict will end up costing local stores and residents about $200k/year.

In other words, it would be cheaper for society as a whole to buy this addict an apartment, food, clothing, and heroin, plus a dozen hours of quality psychotherapy and medical treatment every week, than it would be to leave them on the streets.

Not to mention the fact that everybody that can be lifted out of the gutter also pays taxes. It is rarely the case that large-scale social problems are truly not worth fixing, since they are rarely isolated from society as a whole; there is no dividing barrier between productive tax-paying citizens and degenerates that ensures that their problems don't become ours.

So you should be happy to be paying for someone's mental health treatment, rather than paying just as much for police officers, jails, and a replacement for your stolen stereo.