where this gets frustrating is not when people genuinely dislike foods, but when they've adopted their picky eating habits as an element of their personality. i dated a girl for a while who insisted that she hated certain foods, would eat them in dishes on the sly, then deny liking them to keep up the ruse. it's ludicrous.
naturally, those who just don't dig the way things taste or enjoy eating them should not eat them. but i think sometimes it's easy for people to settle into habits of picky eating from when they were kids and just presume they don't like things, when in fact the human palate changes over time.
ultimately though, yes, you're right--to each his own.