Much as we might agree these workers overall have more money - from whatever source - it does not follow that the pay would go up for crap jobs. The pay need only be high enough above the post tax increase from the UBI baseline to fill the spots. Maybe it won't they populated by people who need to feed their family anymore, but perhaps by college grads who need to feed themselves because UBI is eaten up by their student loan repayment. All we can guarantee really is shifting the bracket of the likely talent pool's need for a few extra dollars. Humans aren't alike in the level of income above which they're no longer in desperation for a few extra bucks.