To be honest, and this is not a MIL bashing, but they mix the classes up because the mil folks are mostly clueless to how the 121 world works. I can't imagine the clusterhump that would happen if a new-hire class was all military pilots with little to no airline/two-pilot crew experience. The Mil guys in my class were very good at flying very cool and fast jets that I could only dream about. But, the folks who had years of regional/121 experience had to answer their questions like "What is a 'ramp'/'ground' frequency?", "What is so bad about EWR?", and "Why is ORD the way it is?"

It was fun helping out the guys around me with those goofy questions, we still answer their questions in the group chat we still have running today, and it helped bond us as a class by working as a team.