I think it's exposure. It's a relatively low-taboo fetish, and (unlike most others) it's acceptable/possible to post/find feet on traditional social media. It's

I think it's exposure. It's a relatively low-taboo fetish, and (unlike most others) it's acceptable/possible to post/find feet on traditional social media. It's possible to post feet pics and accidentally find yourself engaged with a sexual subculture you were not intending to encourage. Also wtf WikiFeet.