I worked for Domino's Pizza when it was still a small, regional chain (Michigan, to be precise--the center of the fast food pizza universe). and I can tell you why it has spread across the world like Zebra mussels.

It's cheap and easy to make, people like it and they will pay a lot for it. Also, when you do it the Domino's way, at least, there is no waste--most restaurants throw a lot of food away, but they don't. That cuts the cost of doing business a lot.

Also, you don't need a trained chef, or even competent short order cook to make a pizza. You can teach a teenager how to do it in about ten minutes. Also, you can't really make the same pizza at home, because the pizza oven bakes at up to 900°F.

Best of all, they bring pizza to your house, so all you have to do is call and have them put it on your credit card.

Basically, it's a profit-driven juggernaut. Abandon hope...