Just curious 😶

Why do people use being pregnant as an excuse to take almost naked photos and post them to randomers online? I understand a pic with the bump hanging out but I don't see the need in photos in tiny underwear, or wearing corsets and stuff all like "will my bf like dis??" 
How would any of us know if he would.
I think it freaks me out more because I've read so many horror stories on people posting pics like this even on their private Facebook pages and their photos later being found on pregnancy fetish sites, being used without their permission for weird Pervy men to get off to.
Sorry about the rant but please be careful girls.