Do cat's eat vagetables

Answer 1

Generally, yes; though they may not need to.

Cats will eat grass, though we are unsure exactly what they get from it. Possibly it is to make up for the grasses and grains normally in the gut of the small mammals they catch and eat in the wild.

Most commercial cat food contains at least some vegetable matter.

Cats have been known to eat bread, which of course is largely grain, and some reportedly will eat potatoes or pumpkins. We do not understand what, if anything, they are able to process from these.

It is uncertain how much vegetable matter cats need in their diet, if any.