You'd give UBI to those least able to work and generate an income.
Rich people from other countries. Especially places where money isn't made cleanly?
Think about it: If someone didn't save their whole life because they assumed social security would provide for a good life, but then they discover that SS hasn't been increasing much at all and the quality of life SS provides is terrible, what are they supposed to do? Suffer? Just because a portion of their generation saved?