Oh yeah- if there's any cat food where they can get to it, they eat it up. I wouldn't let them eat too much as there could be too much salt in it. I give mine canned cat food as a very occasional treat, but never too much at once and maybe once a month. I think if they get into every once in a while there's no harm done.
I usually feed my dog with special dry food or porridge for dogs.
Since I'm a vegetarian, I once thought that making my dog a vegetarian is a good idea. But I have read many articles about it and rejected the idea. If you are interested, here is a link to one of them: https://thepets.net/vegan-diet-for-dog/