Is your bathroom at home split into male/female? When you go to an event or festival do you all use the same ports-potty? It's not about comfort or safety - just discrimination and misunderstanding. Also, I think most arguments are incredibly selfish - YOU don't feel comfortable. I was raised to think of others and their comfort as well as my own. Statistically you are not going to get hurt by a transgender person using a toilet to do a basic human function. Statistically transgender people have high rates of abuse, suicide etc.