Interestingly enough, dinner hours are the times when California relies the most on natural gas for electricity production. Hopefully that changes in the future, but I wonder if all this ordinance does is further centralize natural gas usage at a single point of failure.
That's still a benefit. Pipes leak, so by burning all the gas in the same place, you lose way less gas to leaks, and you also gain efficiency since big generators have less waste than small ones.