I really don't get how people get turned on by feet at all.
I'm okay with people having their own fetishes as long as its consensual, but feet are so sweaty and disgusting.
Unlike hands, you step on dirt with feet. I can understand boobs, ass and thighs, but feet are so far away from the genitals and you normally step on dust and germs all day even when you think the floor is clean.
I know you get germs on other parts of your body too, but I know how bad my socks smell when I take it off, especially after sports, it doesn't change just because they're worn by a woman.