@dadpad,
Oh Great! Another silly Internet Paranoia thread. Look, the IP address is not, and was never, intended to be private. Quite the contrary.
The IP address is like a license plate. It is no more dangerous to let people then it is to let people see you license plate number. It is designed to provide an identification tag, but it doesn't reveal any particularly dangerous information.
Every time you do anything on the internet, your IP address is sent as part of the header information. There is nothing scary about this, it is how the Internet works. Websites can use this information to give you features (like geographically sensitive information).
If you want to do something private, like hide the fact you download pornography or keep people from knowing your are an NRA member, then you have reason to hide your real IP address. There are ways to do this.
Worrying about Able2Know getting your IP address (assuming you aren't embarrassed about your activity on able2know) is on the level of tin foil hats.