Well, I used to have only one (Iams hairball), but we have a kitten here now. Kitten decided that he did not like his kitten food, and kept getting into the big kitties food. And let me tell you, hairball formula was not a good thing for a kitten!
Then also, Kedi decided he liked the kitten food better.

So, what I finally did was get regular adult cat food for ALL of them since they won't stay out of each others.......................
the vet said that it's fine for a kitten to eat regular food, as long as he gets some kitten canned every few days.

Let's see...........that makes 3 types of food. Not to mention all the different treats (probably around 6-7 types)