In the June issue of the Annals of Internal Medicine, Fitzhugh Mullan, Candice Chen, Stephen Petterson, Gretchen Kolsky, and Michael Spagnola, mostly from the Department of Health Policy at the George Washington University (and one from the Robert Graham Center) report on The social mission of medical education: ranking the schools”. For example, a black applicant with average grades and a below average MCAT score is slightly more likely to be admitted to medical school (78.1%) than an Asian student with both higher than average grades and higher than average MCAT score (73.7%).
People enjoy not just the prestige of the Yale community- many famous doctors came from a Yale education, the sterling reputation associated with students simply by being a part of the school alumni, and the wonderful education you get there, but more so the synergy of the entire package.
Regarding your other question - I definitely agree that this would be very valuable to have, though I have not been able to find this info anywhere and honestly, I doubt there is such information compiled/available - once the students are admitted, there is no reason why the schools would keep track of the admission stats for international students separately.
During this time students are instructed in the basic sciences ( anatomy , physiology , pharmacology , immunology etc.) with activities integrated with the medical specialties, allowing the student an overview of the practical application of such content.
If they were going to make another investment in education, I would think the Brethren would favor adding more undergraduate or trade schools in order to provide basic education to more people rather than sink a whole lot of money into a higher education for a few hundred.