depending on how you define "most food around" of course.

I define it as food I see and eat in my home as well as food in the restaurants. I like yummy food and I see no reason to eat non-yummy food.

You seem to think that any tasty food is super-stimulus food. That's not how most people use the term.

Well do you agree that pizza tastes really good?

Depends. There's a lot of bad pizza out there. You can get very good pizza but you can also get mediocre or bad pizza.

Do you agree that (generally speaking) small children LOVE pizza?

I don't see why this is relevant. Small children in general also like pasta and even you probably wouldn't consider it a super-stimulus food.

What is a food or drink which you do consider to be unhealthy?

The dose make the poison. In small amounts or consumed rarely, pretty much no food or drink is unhealthy (of course there are a bunch of obvious exceptions for allergies, gluten- or lactose-intolerance, outright toxins, etc.).

With this caveat, I generally consider to be unhealthy things like the large variety of liquid sugar (e.g. soda or juice) or, say, hydrogenated fats (e.g margarine, many cookies).