The mental healthcare system in California was destroyed decades ago when the "Being crazy is a civil right" crowd, the appearance of psychiatric drugs that made outpatient treatment appear like a panacea and the realization of the anti tax crowd that that would make it possible to close down the facilities all coincided.

There's nothing humane about letting someone live in their own filth under a bridge.

Sometimes it may be more humane to keep them confined when all else fails.

There are some of the camps that are obviously illegal aliens and they shouldn't be here in the first place. Those are pretty self contained and easy to identify. But then you'd be opposed by the "sanctuary city" crowd.