I have a B parking pass and at first I was parking in the designated area. Then I noticed peeps parking on stadium drive and I started doing the same. I still display my B parking pass as it at least signifies that I have the right to be on the edge of that parking lot.
In all honesty, it's kinda dumb. I used to just park in the grass or gravel and sometimes on the concrete hill football stadium entrance in years past. I had my clever spots. As I'm sure many did. In my opinion, stadium drive is perfectly fine to park on the side as long as you at least have a Lot A or Lot B pass.