As I read the OP comment I thought that perhaps in the very same line of reasoning that they would support it being forced upon Negroes to provide services advertising or inviting White Supremicists to a Ku Klux Klan rally. Or perhaps in the exact same line of reasoning a Jewish printery must be forced to make available invitations to a Nazi skin head rally.
Just as surely as some believe that all people must embrace the homosexual agenda, I believe personal choice is the real goal.