It's definitely funny but do you think it could be taken as impolite as well? Also do schools even remember when it comes time for residency?
Personally, I think it's nearly impossible for burning bridges with a med school adcom team to affect residency applications. To even have an effect, here are what the med school adcoms would need to do:
1. Create and maintain a long-standing and exhaustive list of all the med school applicants that burned the bridge or said no to them or whatever. This list will likely have dozens of people within a few years and they would need to keep track of those names for at least four years!
2. Share that long-standing and exhaustive list with all of their residency program directors. At most academic centers, there are dozens of residency programs and physicians are often only PDs for a few years. Getting this list to everyone would take a lot of coordinating effort.
3. The PDs then compare the list from the med school adcoms against the hundreds (if not thousands) of residency applicants they received. To find the same names would be a huge waste of time, even if they found a website or excel sheet to do it for them. I bet that only 25% of PDs would even care to check if they had the opportunity to.
To maintain, coordinate, and verify those same people are not applying to the school's residency programs to the 15+ residency programs four years later would take an incredible amount of organizational skills. No offense, but I have gotten the impression most schools are extremely disorganized through the fact they are most often understaffed, can rarely stick to decision deadlines, or respond to our emails in a timely manner. It is just not realistic that anything we say to an adcom will affect us come residency applications.