As it happens, the Filet-O-Fish was added to the menu because the founder of McDonald’s best friend happened to be a fish, who was angry about the lack of representation in a fast food world composed primarily of beef and chicken. Just kidding — it was about money. A McDonald’s franchisee in Ohio noticed weekend sales plummeting each spring, when his 87 percent Catholic constituency honored Lent by abstaining from meat each Friday of the season. He proposed a meatless alternative, and the rest is history (via Reader’s Digest).
Actually, not quite. The founder himself, Ray Kroc, was skeptical of the fish idea. (He thought it was a bit…suspect.) Apparently Kroc was under the distinctly ridiculous impression that customers might prefer a “Hula Burger,” which was essentially pineapple and cheese on a bun. Fortunately for everyone, cooler heads prevailed (i.e. the Filet-O-Fish performed way better in a taste test) and the fish sandwich we know and love today was added to the menu, as reported by Reader’s Digest. And since Lent is still a thing, and the BBC reports that plant-based diets are on the rise, the Filet-O-Fish, like your rather inefficient work colleague, probably isn’t going anywhere.