Ask anyone who keeps chickens, or ducks, their opinions of foxes! Or farmers with lambs
I am all for biodiversity and the environment, but humans feeding foxes is contrary to the natural process of nature, it encourages them to enter into the urban environment, which is not their natural habitat, it being where they clearly dont belong. Left to their own devices, in the rural environment, nature controls their numbers.
Once humans start feeding them the established, and natural, balance is upset, and they proliferate beyond the numbers that should be present because they dont have to seek out food, they get it provided by humans. A bit like rats really, easy food source results in a ballooning of numbers.