Wharton Health Econ: Not sure why your friends in Applied Econ said there were no interviews for AE. I know for a fact that the admissions committee made many phone calls last year during admissions season to talk to candidates. There were no on-campus interviews, that is true. But there absolutely were some screening interviews made over the phone.
That said, it may be possible that those calls were only made to marginal candidates or people from the wait-list. Perhaps your friends are neither, or they simply didn't perceive the phone call as an interview! But any communication from the admissions committee over the phone is an interview in my book, even if it's just to say congratulations on being admitted... the deal ain't done till you get the offer letter and all!