So when villi are absorbing a chemical slurry into the blood stream they don't actually ask the molecules where they came from. Even if they did it turns out that chemicals don't have memory so they wouldn't get an answer.

Bodies need nutrients, those nutrients can come from where ever. Including a fucking testtube if needed.

Now cats, and to a lesser extent dogs, don't have a body fit for grinding up fibrous matter in order to extract nutrients from it. If you try to feed mr fluffypaws raw kale for instance they are likely not getting many of the nutrients therein because you need to crush the cells.

But humans, among others, long long ago invented crushing the everliving shit out of things. Alongside other processes we can extract what we need, filter out the rest, and mix the necessary components into pellets.

Indeed, if cats have kibble they're eating many vegetables already. Often merely ground. Also plastic and ash, kibble is fucking nasty

Dogs are omnivores though.