For some people, nothing's worse than having to drop a deuce in a public restroom. You have no idea what condition the toilet is in, if it's properly stocked with TP, if anyone will try to access your stall as you're using it, etc.
But this dude probably thought he was in good shape until a brawl spills into the restroom he's in, then literally comes through the stall door while he's sitting there trying to take care of business.
There's a high probability he was good to go after this because he probably had the sh*t scared out of him.