I can't support it.
Addiction and psychiatric issues are something else again. If their addictions are causing them to engage in prostitution or thievery, or their psychiatric issues are causing them to be aggressive or paranoid, then yes, people who are an actual threat to themselves or others need to be removed from the streets.
But mere "homelessness" is not an act of aggression. A surprising number of people are homeless "in transition": lost a job, hitchhiking across the country to find another one; just got discharged from the service, wants to see the country.
If there are no grounds to justify arrest, such as criminal or aggressive activity, just "not having an address" is not an adequate reason to round people up and institutionalize them.
I will just add this to our friendly conversation. Not having an address, a home, a place to live is a fair indicator that a person is in distress. If in addition to not having an address, the individual is mentally unstable and/or addicted to drugs and/or alcohol, they should be rounded up and processed, for their safety as well as my safety. And BTW, the vast majority of people living on the street are psychiatric disabled and/or drug/alcohol addicted. They spread disease and crime. A compassionate society would provide clean safe institutions for these folks to get appropriate treatment. Turning our backs on them and leaving them in their pathetic condition is not compassionate. I am not talking about the recently discharged service man or women hitch hiking across the country to see the landscape. I know they are everywhere, but funny, I never see them. It's just the bums and the psychos that need help.