I know first-hand living directly across the street from the library in a pretty nice neighborhood here in Los Angeles. On weekends at least 1/3 of the patrons are homeless. Libraries are safe, open for long hours, and offer everything from public bathrooms to a place for people to search for online job listings. I think libraries are fully equipped and ready to address community needs, and this for sure, is another community need.
So it is no surprise that libraries are coping with a large number of patrons who are homeless or have mental illnesses. Public libraries are, after all, designed to be welcoming spaces for all.