While I personally find this policy abhorrable, its certainly a private communities right and perogative to set a curfew. I see it no different from a parent choosing to raise his child under given dogma (atheist, agnostic, monotheism, pantheism, whatever) only it's for a city.
I sure know I'd voice my opinion and move the hell out of such a shithole. No offense. If the common view of my fellow townsfolk is one of bigotry (particularly the elected mayor), it's not a town I belong in. Let the bigots be bigots as is their right but I shan't be counted among them.