Hello. Cats are, indeed, unusual creatures. As far as I have seen, some cats are very picky about what they eat. While Bear, our current cat, has been on moist food sometimes and dry food at others, most of it he’ll eat only when he’s hungry enough. But, no matter what we do, he always goes directly for the Meow Mix. Our cats before him, Joseph and Emma, preferred wet food over dry, but would go directly for 9 lives most of the time. When they were there, the little kittens I used to care fore behind where I work took whatever was offered, but went directly for Friskies. I know I can say a lot by this. If all your cat eats is dry food, it’s okay. You don’t have to throw out the dry food, since it doesn’t spoil at all. If you’d like him to eat moist food only, then pick up the dry food for a few hours, then put the moist food down. Don’t expect him to go for the moist food right away, since change is something cats don’t really get accustomed to very fast. But, yes, it’s just fine if all he eats is dry food. There’s nothing wrong with him unless he starts throwing it up or doesn’t eat all that much at once or over a day’s time.