Originally Posted by 678flyer
I may be wrong here, but I always thought that the airline continues to own the miles, not the customer.
That is, of course, the airlines' self-serving position which I believe is itself unethical. How supportive would you be if you received an award from your employer for being a loyal employee, and then your employer attempted to restrict your use of such reward?
Miles are the property of the airline - account holders are granted usage privileges, but not ownership rights. In effect, the OP tried to sell something he did not own.
Totally irrelevant argument IMO. I could argue that the OP was selling usage privileges, which he does own by your definition.