Let's have a focus group of 5 years old and see if they prefer Doritos or fresh halibut.
What culture were the 5-year-olds raised in? What foods were they exposed to? Seriously: food preferences and cultural preferences start developing at a much younger age.
Even foods "all kids love" may not really be so. My son hated sweets until he was 3 years old. HATED them. We gave him a piece of his first birthday cake, and he spit it out and literally scraped the remainder off of his tongue with his hands. We never tended to have sweets in the house, so he was never exposed to anything like that before. I think he had the same reaction I do now to regular Coke -- it's so sickeningly sweet that I'm repulsed by it. It's positively unnatural.
My kid instead barely experienced refined carbs probably for the first couple years of his life. I baked at home for him the only bread he consumed. We weren't trying to "hide" sweets from him -- in fact, we offered them to him quite a few times. Inevitably, he'd take a small bite of the cookie or whatever and then put it down. We didn't eat a lot of the stuff either, so it didn't matter to us. One thing his mother really likes though is ice cream, so she kept trying to introduce that, and he'd spit it out.
His favorite foods when he was 2 included things like sauted bitter greens and eating beans basically right out of a can. Oh yeah, and bacon. And just about any kind of meat. But sweets? Absolutely not. Any kind of "chip"? Once he was old enough, we offered, and he hated them. It wasn't until he was 6 or so that he actually started to be interested in things like potato chips, but Doritos would still be summarily rejected.
He simply grew up without a lot of processed foods in the house, so they were unfamiliar and weird to him -- often with extreme and bizarre flavors, so he rejected them.
So weren't we shocked when for his 3rd birthday party he requested cupcakes! Huh? The kid who for years rejected every sweet thing we offered for years? Turns out that unbeknownst to us, his new daycare facility (the first time he had been in regular daycare) served cupcakes to all the kids as a treat on every kid's birthday. So he came to associate cupcakes with celebration, and that was finally enough to overcome his revulsion of things that were too sweet. It was the ASSOCIATION of sweets that made them appealing, not the flavor by itself. (Note that he loved stuff like fruits since he was a baby... it was only the stuff that was a lot sweeter like candy and cookies and cakes that he rejected.)
I'm sure not all kids would be like this, even if they weren't exposed to as many processed foods at a young age. But keep in mind that it's NOT flavor alone that makes processed foods appealing -- it's what they do to your body. They are cheap easy calories, often packaged conveniently with little or no preparation, and they cause metabolic reactions that often lead to overeating (especially stuff like Doritos, which fool your body with flavors that mimic savory stuff but only provide cheap carbs and fats, which leads your body to say, almost literally, "Where's the beef?" and thus encourage more eating....).
If you don't get far enough with processed foods to experience those reactions, the taste alone may not be enough to hook you. Try spending a few months away from the "junk food aisles" and learn to cook things for yourself, and see how much you really miss. Sure, there are a few specific cravings I still may get for the junk food stuff, but mostly I now find the flavors less significantly appealing than "real food."