Governments try stuff like that pretty regularly (you can only buy certain things with food stamps, etc), but it's typically expensive to administer and inherently prone to abuse. Buy groceries with food stamps, sell groceries, buy drugs. On top of that, it's just inherently difficult to structure this in a way that's fair and useful to every person. If I inherited or built myself a nice rural home, I don't want a government-issue apartment - either instead or in addition to what I have. Do I get nothing? That's unfair. Do I get the stuff I don't want?
"Lump sum in cash" is the most flexible and equitable system. But then - and that's a major problem with UBI - you end up with people who spend it irresponsibly and then need help to survive. So you end up with UBI in addition to all the existing social safety nets.
"Lump sum in cash" is the most flexible and equitable system. But then - and that's a major problem with UBI - you end up with people who spend it irresponsibly and then need help to survive. So you end up with UBI in addition to all the existing social safety nets.