Why does MIT have a quota for internationals?

@bodangles Regarding number 1: I understand that, but I’m wondering why it’s a hard quota? Schools like HYP don’t have a quota, yet still internationals only ever form a maximum of about 11% of their classes. With respect to number 2, even if they didn’t accept any internationals at all, they could still hypothetically accept a fully american class in which every single student requires full aid, so I’m not sure that would be the reason (unless internationals, in general, need more aid than the average US student). Also, none of the other 5 schools that are need-blind for internationals have a hard quota.