Okay, I saw someone mention captain D's, but no one mentioned Long John Silvers (the much better of the two in my opinion. Both are fast food chains that sell deep fried fish and fries (or chips). I have noticed that you can find smaller places like you mention the closer you get to large bodies of water. I remember seeing a few in San Diego and Galveston when I used to live there, typically within a few miles of the beach (that includes piers).
Plus remember, most of our national chains here in America started off as a small locally owned business, over the years they evolved into their modern standard of convience. Here in north Texas there is even a proposal to ban drive thru windows for part of the year, it would really suck if it passes, hell we even have drive-thru beer stands for crying out loud.