*Originally pizza was not really a dish you looked forward to. It was like stew. You made it to get rid of all the leftover crap from previous dinners so as not to waste food. Crust, sauce, yesterday's meatloaf,** the salad remnants from the night before, crud, these peppers look like they're gonna go... and cheese to hold it all on there!
** Be aware that this part is made-up. Leftovers didn't exist in plenty the way they do now, there were no refrigerators. I imagine if you had some peperoni but not enough to really feed someone for a meal, that would go on there but that sounds way too appetizing to get my point across. The truth is, olden-day leftovers must have rocked.