I feel like the fact that they only eat cake is just for balance. Snails in real life eat anything that they find and many species like eating literally feces, actually there are many parasites that plead to snails as a result of them eating bird poop specifically the zombie snail eye parasite. Anyway I find it ridiculous that this little snail demands and will starve without cake, even though it literally lives in the wilderness where no cake is found.