The idea that an aversion to ketchup on hot dogs has anything to do with being “sophisticated” is total nonsense, yet has somehow gained traction in this thread. The reality is the exact opposite; it’s all about basic compatible flavour profiles, as when I said earlier that cheap yellow mustard is perfect for hot dogs, even though I use Dijon for everything else.
Ketchup has a rich umami flavour profile (which is one reason kids like it so much) which makes it a delicious enhancement with certain foods and terrible with others. I don’t use it often but it’s essential on basic chesseburgers (though not necessarily on some of the more exotic gourmer burgers), with grilled cheese sandwiches, scrambled eggs, even french fries if you must, and, yes, your basic plain or cheese omelet.
The latter may have given rise to the trope of the boor ruining a beautiful omelet by pouring ketchup all over it, and hence the “sophistication” angle. But that’s true only if said boor ordered a first-class omelet at a fine restaurant, the kind where the chef prides himself on creating a balance of delicate flavours that is a culinary masterpiece, and the customer then dumps ketchup all over it. Men have been hanged for less. But that’s not the same as adding ketchup to what is basically scrambled eggs and cheese. It’s more like Donald J. Trump insisting that his steaks be so incinerated that they resemble the grayness, dryness, and toughness of shoe leather, and then trying to rejuvenate them to the resemblance of something edible by adding about half a gallon of ketchup.
So what is it about ketchup on a hot dog that so offends our gastronomic sensibilities? I would posit that it’s a combination of the sausage itself, plus the other garnishes that it’s naturally compatible with. The sausage tends to be spiced and heavily smoked, hence the appeal of the sharp acidity of yellow mustard, and the equally sharp flavours of things like savory relish, fresh or balsamic onion, or sauerkraut. I would no more put ketchup on a hot dog than on a cold cut sub or sandwich. Lettuce, tomato, and mayo, absolutely. For certain sliced meats, maybe a light touch of Dijon. Ketchup? Never!
I agree. I didn’t mention sauerkraut in my list of essential hot dog garnishes because I don’t usually have it around so it didn’t come to mind, but it’s great with hot dogs if you have some. Even better if sauteed and browned on a stove top with some bacon bits. The crunchy texture and mild acidity is perfect for dogs. Just don’t get any ketchup on it or near it! 