I think there were more admits in R1 this year because the application pool spikes this year and admission is becoming increasingly competitive. Schools have been able to fill their student pool as early as R1 because unexpected quality of applications.
Bschool is itself a business. '我觉得在美国现在这样的政治气氛,在obama发话希望美国人接受更多的教育,Top学校不考虑多给美国学生发admission才叫鬼了呢。' is, I believe, unrelated to business school admission decision.