Those grad programs are too large. The main draw for international students is often the visa, and the universities treat them as cash cows, often providing poor quality product.

A friend of mine in a graduate physics program recently told me that he felt that 90 percent of the students lacked the aptitude to capitalize on the program at all, but that the university was financially incentivized to keep them in.

Obviously, this applies to both foreign and domestic students, but the point is that these programs are grossly inflated.