Some of us prefer separatism (because we have superior group traits that provide us premiums) and some of us prefer integration (because we can gain from superior groups or inferior group discounts).
So it is in the interest of people from inferior groups and often with inferior traits to seek the benefits of superior groups.
The question is only whether it is of benefit (profit) to the host, or harm (loss) to the host. And in general transfer of professionals that reduces the price of professional services is of benefit, while transfer of labor which reduces the price of labor is of harm.
The simple reason being that lowering professional costs and raising labor costs is in the group’s interest.
My argument is that groups must pay the cost of domesticating their own, and if they cannot domesticate their own, and worse, if they export their own – causing externalities by doing so – they lose the reciprocal obligation to permit sovereignty (self rule).
This is a terribly simple problem: Pay for your own costs – one way or another.