It's probably stuff like this on every level:

https://www.nydailynews.com/news/politics/new-york-elections-government/ny-comptroller-tom-dinapli-audits-brooklyn-homeless-shelter-waste-20220919-rvczwi3zhjcsppewpey4ivuaxi-story.html

Those shelters also provides "other services". For example, imagine how they bill health services for homeless people who lacks any health coverage.

I wouldn't be surprised if a typical shelter-provided "health care check-in" bills the city $400 for a 3 min consultation.