That's true, that's a game played by the previous owner, sorry. There's no cap or a hidden max value for arena capacity, there's only what you see and the game engine uses those same numbers. Since the games were played at the same or similar prices with some small variations in fan's enthusiasm, it's no wonder the attendance is so close to each other. Being at 100 or 97 is just a coincidence. Bring the prices down on the next update and the attendance will go over 100.