When it works, it’s actually a great boon for the individuals at question, as well as dramatically out-competes alternatives on price, as there’s a four orders of magnitude difference in price between the cost of buying and building housing and shelters, particularly in some of America’s most expensive and overzoned real-estate markets, versus buying them a ride home to somewhere they’re expected. [1]
That said, these programs have mixed results - sometimes great and life-changing, sometimes ruinsome due to poor vetting of the opposite side and being used as a high-pressure removal tactic [2] - but cities have broadly embraced doing it because in either case, it is effective at the political goal of moving one’s homeless problem somewhere else.
[1] https://www.sfchronicle.com/sf/article/sf-homeless-bus-homew...
[2] https://www.theguardian.com/us-news/ng-interactive/2017/dec/...