I suppose the first fast food I ever ate was at a White Castle (obviously not in Dallas, since the nearest approximation in this part of the world is a lone Krystal .. and they ain't the same). My father always liked White Castles, but not for the ambience. I think the burgers were 14¢ each, and (like now) it wasn't uncommon for someone to order a dozen or more, then apply some spicy mustard and pop them back like so many M&M's.
I also remember when the first Burger King came to town, with their "Have It Your Way!" mantra. Back then, we pushed plastic trays along a line of metal tubes (think "cafeteria") and watched as the burger was assembled right in front of us.
"Hold the pickles, hold the lettuce, special orders don't upset us ..."The idea that we didn't have to endure a burger the way Burger Queen (yes, that was the Big Chain where I grew up) prepared it was mind boggling, even for an 8 year old. Burger Queen has now been relegated to The History Books, since they failed to carve a niche deep enough to stay in business.
12 Oct update: I'd forgotten what replaced Burger Queen in my area: it was a short-lived chain called Druther's. Not sure I ever went inside one, and have no clue what their target cuisine was ...I also remember eating at H. Salt Fish & Chips and marvelling at the authentic way they presented your order -- in a sheet of faux newspaper, and applying malt vinegar to the fish! I wonder if I was genetically predisposed to like that, being partially of British ancestry and such? Did I mention I had herring-on-a-bagel for breakfast a few weeks ago? Maybe I'm part Jewish?