How come the airlines couldn't post a sign at the check in that says, "We reserve the right to refuse service to anyone". After all they do own the airplanes. Right? Why is the TSA determining who can ride THEIR airplanes and who can't? The AIRLINES should have a person at the check in line that determines who can ride on THEIR planes? How come the airlines couldn't tell someone "Thanks but no thanks"? Take your business elsewhere. No explanations except we refuse to service you because WE OWN THIS AIRPLANE.