In most cases, yes. Supermarket chains prepare flyers and advertisments for their entire chain of stores in a region, and advertise prices that are posted in each of the stores. Regardless of whether products are advertised, supermarket chains usually require their stores to post the same prices (again, in each region), because they have central purchasing and so provide the products to the stores at a uniform cost.
Stores have some pricing flexibility on certain items, such as meats. And individual stores may have their own Specials on some items, in particular meat, dairy, and produce. Individual store and department managers may also post their own prices on damaged items (dented cans, broken boxes, etc.) or items at or past their sell-by date. Even there, the chains try to enforce uniform mark-down or discounting policies among the stores, so that "Yesterday's Bakery" is, say, 50% off in all stores.
