The thing is being gay or lesbian or bisexual is about sexuality.
Being TG is about gender.
Sexuality and gender are two different issues, but that's a post for another day.
If the TG community really want to try and make a point it should be that we are not part of the gay community. We are tagged onto the end of the gay scene because "society" does not know where else to put us and because"society" assumes that we are gay.