Unfortunately most are drug addicts, alcoholics or mentally impaired but it's what happens in any major city in the world, unless you want to live in Texas where the Police run them out of town with beatings & other violent methods. I have to say, it's not an option for that kind of treatment in my opinion. I moved here in 1991 from Dallas,TX and I never really had the experience of homeless people until I moved here but after spending the first few years renting in the Tenderloin (because it was all I could afford) my view softened a little.Yes they are disgusting, perverted, inconsiderate and loud but they are still human beings. If I wanted it to change I'd just continue to call for the police continuously until perhaps they would disappear, even if it took years.