Attendance numbers. Even though they draw less fans to Gillette than their home stadium, the potention to draw more is there. Something I'm sure to Do with d1 requirements.
That said there was well more than 5000 total fans. There was 5 sections of around 1000 each just filled with BYU fans on their side of the stadium. UMass prob had about the same amount. Add the band kids and it was around 14k I'd say.
Having the fans all packed in made it seem more crowded than it really was. Was nice also to walk around the stadium and take in views from all over. It really is a good place to watch a football game.