Probably a cultural thing. California is more "cuisine" and health focused, hence why it's easy to find good salads, sushi, farm-to-table, vegetarian, etc. East coast and midwest is more takeout focused, therefore better sandwiches, pizzas, wings, etc. Not hard to do well when the handful of competitors in your area are also crap. The only takeout that is consistently better in California is Mexican.
Could also be water quality. Dough is roughly 1/3 water. Most California water is awful quality with high pH and carbonates. Crap water makes crap dough. A sandwich or pizza is only as good as the bread or dough it's cooked with, and I will die on that hill.