we sit next to a student section in ticketed seats. Every seat had a shirt on it. As the stadium filled up and the students started arriving they casually walked over and just took a shirt off of a ticketed seat and walked back to the student section. A few others went through nearly every shirt looking for one that wasn't a M that would fit them, they left most on the dirty ground as they went row by row.
But that's OK, Crush4 says they're free anyway so no need to look for your size. Complainers.