Problem is much more complex than what it seems. Los Angeles really has become "Los Assholes" (I renamed it after living here for about 5 years).
Unfortunately many of the homeless are also "Assholes" and if you want to gain a basic understanding of this problem, pay a visit and drive thru the flower district, turned Skid Row, after 6 pm, when they set up camp.
Although you can't say this about every homeless person, by any means, the ones downtown would probably not accept help, even if you offered it to them. In general, these folks are very sick, physically and mentally. We are talking about the kind of people who get into a fistfight with a mailbox, because the mailbox disrespected them.
Granted you can round them up and put them in a mental institution, but you have to have the staffing, and the collective will, on the part of this population, to take medications with awful side effects and to live basically incarcerated. You also have to have the will, among the taxpayer and health systems, to fund such an operation.
And you have to have very special people who are willing to help folks who they might place on a gurney, and when they turn around to check on them, the patient tries to take his or her hepatitis shit-infested fingernail to the responder's eyeball.
Perhaps this Wu-Flu might be enough to persuade the non-crazy homeless to give up panhandling and soup kitchens, and life a settled life and be boring. Who knows?