Most gays that I know are Lefties. While the Left does not automatically support unions the Democratic Party is 100% the pawn of modern unions.
Union supporters have been running a periodic ad that is false. Unions claim an important role in child labor, safety and time off laws about labor.
This is historically not true in the United States. It was the movement around women's suffrage and particularly Jane Addams and the immigrant related Settlement Movement that created the core labor rights at state and national levels.
Not only do the unions come to this issue late, but they were segregated for over 50 years. During the early battles labor rights for children, women and workers in general, unions were out fighting among themselves and with anarchists most of the time.
The relevance to gays is what I saw with my own eyes. In the mid-1960s, my close friend Ruth Kadish was appointed by Gov. Brown to the California State teachers personnel board.
At that time, it was policy to fire any teacher who was arrested (not convicted) for homosexuality (caught in a public bathroom). Ruth lobbied her board to reverse this policy for years.
What is relevant to you if you are gay and support any union is that two strong California teachers unions opposed Ruth at every step. The unions supported firing gay teachers.
Unions are not your friend, even if you are in one, unless you have seniority or are incompetent.