Tradition, culture and society has dictated that standing for the anthem is a sign of patriotism, and respect for our country.  I can't rewrite societal norms and say that one thing means something else?  Can I flip a bird and have it mean peace? No.  Can I kneel and say it means something other than disrespect for the country? No.  Do you have the right to disrespect the country? Yes.  Do I have the right to be disgusted? Yes.