The NFL ones can be a bit of a con, they’re allowed to pipe in 70-80 decibels of crowd noise before the actual crowd make any noise at all.
Again, 'decibel' is a meaningless indices and tells you little to nothing. There are weightings, frequencies, averages and an awful lot of other things to account for.
You can have a noise of 90+ decibels a few feet away and you won't hear it until you put your ear right next to the source.

