You are still failing to see the issue -- you need permission from the owner of the trademark to use it commercially, with a few very limited exceptions.
In regards to a domain name - the harm could be (1) what if I dont want YOU using it; (2) or I wanted to use it myself; or (3) I would have made more money using it than you; or finally (3) I wanted someone else to use.
Michael
www.AdultBizLaw.com