Why? Unless you can show proof that most of the homeless in SF and LA are locals who fell on hard times rather than junkies who moved in for better weather and benefits, shipping them out seems completely reasonable.
And where will you ship them to? Smaller cities don't want them and they'll be inhospitable enough they won't want to be there either - they'd rather ship themselves back where they can stay close to their drug sources and still rotate with their panhandling around enough that the locals don't get too familiar with them.
So if you want to do something about the vagrant encampments being in the city you live in, the most effective thing that you can do is move to where they aren't, which is what everyone else who cared that much about it already did long ago.
Morality and optics of forced relocations aside, because it leads to cycles of retaliation by the places they are shipped to.
> Unless you can show proof that most of the homeless in SF and LA are locals who fell on hard times
I don't know about LA, but this has been studied for SF, repeatedly, and they are.