Lame argument. If a video rental store suddenly published a list of all the naughty videos you've ever watched, would that be OK because you opted in to their service, gave them your name etc.? It's their business, they can do whatever they want right? What if we had a private conversation and I emailed it to all your friends a month later, would you be fine with that? It's your fault for talking to me in the first place right?

Isn't it common courtesy to respect a person's privacy or at least be clear about it?