When I was researching the Mellow Mushroom operations, including studying the MM menus, I learned that MM sells both Build Your Own pizzas and Specialty pizzas. There were a total of 14 different Specialty pizzas. In my reading of Yelp reviews for MM stores all around the country, it seemed to me that a large percent of the diners in their stores ordered Specialty pizzas. I did an analysis of the pricing of all of the MM pizzas, from which I came to the conclusion, rightly or wrongly, that the pricing of the Build Your own pizzas was perhaps set such that diners would choose to go with Specialty pizzas rather than the Build Your Own pizzas. For this upsell to work, the margins for the Specialty pizzas had to be better than for the Build Your Own pizzas.
In analyzing the different sizes and prices of the MM pizzas, I also came to the conclusion, again rightly or wrongly, that those prices were set to encourage diners to order larger sizes than smaller sizes, for example, going from a 14" pizza to a 16" pizza where the margins might be higher. This really isn't much different than consumers buying things in the supermarket in quantity to save on per unit cost.
My recollection is that I used the menu at the MM location you frequent.