For the longest time, I never let on that clowns creeped me out. Other things that I dislike are dolls, ventriloquist dummies (which I perceive as demons), and manikins.
It is only within the last couple of decades or so that people have been more public with these fears. I think the fear/dislike has always been there; people just kept it quiet. Many people dislike things that look human but are not. Although I guess that clowns technically *are* humans... they just mask it.