I know Revenge of the Nerds very well. Very well.
The bleachers in Tiger Stadium was sealed off from the rest of the stadium. Underneath the bleachers in the lower deck was where they stored things so you couldn't go down there. In the rest of the stadium you had street level concourses/concessions as well as at the top of the lower deck. If you sat in the upper deck you used those. But if you tried to walk all the way aroudn the stadium they had chain link fences with an attendant near each side of the bleachers. It was like being in prison. It was the lower level concourses that had some hallways and doors that you could sneak through. It was cold and damp everywhere and had a smell mixed of onions/peppers/beer, and probably piss.
Coleman Young famously shut down the bleachers because people were getting rowdy. We sat there for opening day in 1995, after the strike, and the season started later so it was nicer out. Things got crazy as fans were kind of rebelling. Women were flashing people. People ran on the field.