My mother said she used to catch me sitting behind the couch with a spoon and a large jar of French's yellow all the time. Evidently, I was a mustard head back then, too. I dearly love mustard now. There're usually 7-8 different kinds of mustard in our fridge, all for me.I went through phases as a kid. At one point, I LOVED mustard, put it on everything. Hated mayo. Then I started to LOVE mayo and put it on everything, and hated mustard. Or maybe it was the other way around. But anyway, now I like both but I don't put them on everything.
It's natural for kids to be picky, as they have more sensitive taste buds. It's also a survival mechanism to prevent some poisonings. But Americans tend to beat it out of their kids (literally or metaphorically), which is horrible, but also very ingrained in the culture. People act like a picky kid is going to grow up to be a terrorist or something :/.