Crowds are everywhere you go in the summer, not just Oshkosh. I hate crowds and traffic too, so I understand where you're coming from.
There is a considerable commercial element there, but there are also lots of other things to see and do. I like to see and hear the airplanes, take some workshops and FAA WINGS classes, talk with people and learn new things.
I'm just starting to get into floatplanes, and haven't ever been to that side of AirVenture, but I'm planning on stopping by there this time. Looking forward to going and making memories with my wife (it'll be her first time there), but at the same time, dreading the crowds, traffic and overpriced foods and souvenirs. Hope that makes sense.