One could easily write a consent form and forge your signature. That would be illegal, too, yes, but they could still do that.
A site like College Humor must be posting illegal pictures every single day. I knew a weird kid who had a boner at a pool party while standing behind some girls, a picture that was posted on College Humor. When he was shown the photo, he didn't know what to do, so someone suggested contacting the site admin.
One has to wonder how this website still exists. They must have several lawsuits pending against them.