We got Lucky Charms ONCE, but otherwise we really weren't allowed to have super-sweet cereal. I still have never had Cookie Crunch, Cocoa Puffs, or Cap'n Crunch. I've also never had a pop tart, though there was a period where my family went all-in on toaster strudels
Mostly likely we weren't allowed to have anything that was too expensive. Anything chocolate was a special treat. Anything marshmallow we had to try every once in a while to remember they were gross - but they looked so amazing in the commercials.