I seriously doubt MU-COM offers secondary invites for the money. If you're invited to interview, you'll see they spare no expense when it comes to giving your application the full attention it deserves. Admissions representatives are able to recognize most people on sight, and some can recall your specific details on a whim. Although some schools give the distinct impression their application cycles are a cash cow, I don't believe this is the case with Marian.
Many applicants improve their stats during the application process. Last cycle, I was offered a secondary with less than a 3.2 sgpa and with exactly a 24 MCAT. During the cycle, I took a great number of science courses and raised my MCAT, eventually earning an interview and alternate list spot (although that is where I remained). I believe MU-COM reps genuinely believe in a holistic review, although no school can escape the necessity of good numbers.