In a battle of the bands sitch I could see how they might want to level the playing field, how can you do 'battle' without your weapons??
Some guys cultivate their tone as much as their technique and that 'comfort factor' playing on your gear, your able to pull 100% of your best stuff from has got to be better than playing at 80% on someone elses burnt out rental crap.
Maybe if enuff bands refuse to play places like this the trend will change...

forcing someone to endure strange and crummy gear cause the sound guys too fkn busy to soundck. everyone? what kinda shit is that?