UBI is supposed to replace other need-based social programs such as disability, welfare programs, government housing, etc. The entire point is that the money from those programs, which collectively have quite a lot of waste, goes into UBI so everyone can participate in society on a more fair level.
There's basically an entire industry dedicated to denying and minimizing payouts. With UBI, that entire industry becomes obsolete.
If UBI is done properly, it replaces those other social programs. The payouts are bigger and for more people, and the program administration costs are smaller.