How can fox be obese living in nature, not at the zoo?

How do you think? Could anyone feed it? And what can they eat, except rodents, birds and other living creatures?How can fox be obese living in nature, not at the zoo?
Obese animals are rare in nature, because obesity is a disadvantage for the animal. However, if there is an overabundance of food than it is possible that an animal may be obese. In the zoo obesity is much more common. We can overfeed some animals and the animals have much less exercises than in the wild. In the wild they have to hunt for food which causes them to inevitably loose calories.How can fox be obese living in nature, not at the zoo?
If there were a fox anywhere near me, I would be feeding it until it was perfectly round with its legs not able to touch the ground.
If they were near a large resource of food such as a landfill, they could become obese. Foxes are omnivores so anything of value foodwise could be consumed.