They put "hamburger" on their pizza.
I came down to CT....slices were triangular...they would hold their shape. Toppings were placed on the pizza...not dumped on with a bucket loader. There were no "inside pieces".
Plenty of square pieces of pizza in CT too. As a kid growing up in CT I remember having more pizza cut into squares than triangles. I also used to eat a lot of hamburger on pizzas. I don't think I've done the hamburger thing in a while, but my favorite place in the town I live in now does the squares. The inside pieces are better once it's cooled down a little...