I agree that people leaving food out feeds wild animals and it will just keep drawing them in. But I would protect my dogs before being concerned about a wild fox. Just my opinion
The way to keep a dog safe here is to not leave it out unattended, and have it live indoors-considering the coyotes, occasional cougar and wild hogs in the woods, anything else would be temporary and bound to cost your pet’s life eventually-there have actually been dogs dragged out of electrified fences and killed at night. The wildlife is treated with respect and caution by me-I’m just glad we don’t have bears here...