People ask this question way too many times...
Penn does not offer interviews to everyone, they offer them based on availability of alumni who live relatively close to you. They also do not offer interviews based on how interested they are in accepting you, it is almost randomly selected. Someone who has no chance of getting into Penn could get an interview over someone who seems highly qualified.
I live IN Philadelphia (not the suburbs that consider themselves part of Philadelphia), right where Penn is and where tons of alums are, and around 10-15 people in my class applied ED to Penn. Only about a quarter of us received an interview, and some of the people who got one are definitely not as academically qualified as some of the others who applied and didn't get an interview.