A hundred years ago it was much more expensive to travel, and governments less forgiving about cultural differences when enforcing local laws against immigrants. That doesn't mean it would be a sane policy today.

To put it another way, would you be okay with the entire Chinese army "immigrating" in preparation for an attack, as long as they all represented themselves as private citizens during the trip?

If not, then you agree with immigration restrictions in principle, "and we're just haggling over the price".