There are a lot of these combo restaurants free-standing. Pepsi owns Taco Bell, KFC, Long John Silvers, Pizza Hut, and several others. I once added all the ones I knew about together and came up with the ultimate fast food place, a Long John KenTaco Hut &W.

They may not have had whatever special that was anymore but didn't have anything to replace it, so they put the sign in backward to prevent bright glaring lights... Or someone just didn't realize the difference between door open and closed.