Cause it's fun...?
Aviation is a field full,and i mean FULL, of *********s, smarta$$es, and unnecessarily cocky people. I am constantly reminded of my fraternity days when I'm in a big group of pilots. That's just how it is.
Point is, most of us love to ragg on each other. It's fun, and it gives us something to do. You just need to suck it up and get some thicker skin. There is nothing necessarily wrong with graduating from riddle, but it's easy to poke fun at you guys. Just take it in stride and smile....