I live in Oakland and moderate (mostly post) to the Oakland community.
I don’t recall all the details right now but… I think they tell all the people leave and then throw everything left in the trash.
EDIT - Here is a story our local NPR station - https://www.kqed.org/news/12006541/sfs-homeless-sweeps-have-cleared-over-1200-tents-where-are-people-going
SF says the people they are doing this to have not accepted the city’s very limited options for housing.
There was recent article (help me find it) detailing there are over over 200 SF non-profits focused on housing funded by less than 10 govt agencies.