Directly, it usually it leads to poor working conditions when you have non-residential workers, especially ones in a quasi-legal status.
For factories, you sometimes have the problem of the factory shutting down after the locals become dependent on it.
For migrant working, it's hard on the children of the family and it causes tension between the families not participating.
Philosophically, one could argue it's exploitation and is very close to slavery except the small amount of pay. Until this type of work is extinct I don't think one can morally campaign for UBI can you?
Currently this type of work is apparently necessary so we've accepted that the system cannot either pay the more wealthy citizen's wage nor up the wage of the foreign workers.
Is there a demand to up the wage of these non-represented workers that make far below minimum wage?
Is there a demand to up the wage of minimal wage for citizens and are the foreign workers mentioned?
Is there a demand for UBI for citizens to not work at all while foreign workers pick up the slack?