I have used Airbnb several times though. I find silly to worry so much about how much "they know" about you. They might as well know everything, with such a huge database there is no way they would especially look out for you. The state, for instance, knows everything about you. Unless you accept to get promotion emails (which you can easily switch off) there isn't much they can do with your information.
RE: Offender of Privacy and Traffic Pollution: Airbnb