I have very hard time believing it. Food that I consider above average
may be a little more expensive, but mainly because it's much less mass-produced. And there's better quality ice cream that costs roughly about the same (though much harder to find), and terrible quality ice cream that costs more. We don't have to go far - Coca Cola earns billions selling basically caffeinated sugar water. Not because people don't have any money to buy better drinks. Because people want to buy specifically sugar water, because they have learned that's what cool people drink.
Finding a working ketchup formula may be not easy. But you have to do it once. Then that's it, you can sell it forever. And it doesn't take that much. As well as it doesn't take it that much to not just stuff tomato paste with as much sugar as chemistry would allow and call it "ketchup". And yet, mass brands to that and a lot of people happily buy it.
Better stuff may cost more, because of smaller volumes and better quality controls, but not 5x. At least not all of them. I just checked the list of ketchups in Whole Foods. Heintz is 17c per ounce. 365 brand is 8.7c/oz. Others range from 18c to 73c, pretty much equally distributed. Yes, there's one 5x brand - but that's one, out of a dozen. And that's just one store, I'm sure there are more brands which will occupy the whole gamut from 1x to 10x (I am sure somebody somewhere sells a ketchup for more than a dollar per oz, even if I haven't seen one).