Ham and pineapple on Pizza is famously offensive to Italians and oddly not mentioned in the article (probably because it is such a cliche). Yet it works. And those saying fruit has no place on a pizza: tomato is a fruit. Some of this grammar is simply irrational habit.
Sometimes food rules are even encoded in religion. E.g. Halal and Kosher food rules are pretty strict about what you can and cannot eat and how things should be prepared. Or the Catholic habit of eating fish on a Friday or indeed serving wine during church.
Going against the rules can yield nice results. Fusion cooking is a thing. Also, Neil Stephenson wrote about a North American thing called recombinant cooking. I'm not sure if he invented that term but it refers to the practice of cooking food with store bought processed food (e.g. rice crispies) and recombining it with other ingredients. Basically, it's the notion that some people only know heavily processed food and use them as ingredients.
In botany, sure. So are Peppers, Beans, Peapods, Avocado, Squash, Zucchini, Cucumbers, Olives, Corn Kernels, Pumpkins & Nuts.
In culinary terms, though, most of these are vegetables - none of them are fruit. Mostly because none of these are sweet in the same way as fruit. I think tomatoes get brought up because their sweetness ranges between "vegetables" and "fruit".
Yeah, the Japanese language for classifying things as sweet, sour, salty, bitter, and umami might be more useful. But that kind of is the point here, a lot of this stuff revolves around these arbitrary classifications that we've used historically and culturally and you get interesting results when you mix that up a little.
Which is why taking sweet and salty things like pineapple and ham and putting them on a Pizza is completely normal to some and offensive to others even when using other, similarly salty and sweet ingredients is considered normal to them.
Sometimes food rules are even encoded in religion. E.g. Halal and Kosher food rules are pretty strict about what you can and cannot eat and how things should be prepared. Or the Catholic habit of eating fish on a Friday or indeed serving wine during church.
Going against the rules can yield nice results. Fusion cooking is a thing. Also, Neil Stephenson wrote about a North American thing called recombinant cooking. I'm not sure if he invented that term but it refers to the practice of cooking food with store bought processed food (e.g. rice crispies) and recombining it with other ingredients. Basically, it's the notion that some people only know heavily processed food and use them as ingredients.