Probably because they want to avoid the children getting abused at home, or worse
Most abusers do not wait for some specific reason to start abusing. I would be interested to see data how many abused LGBT kids were never abused before they came out to their parents.
Edited in all of the above.
Hmm, I wonder what would happen in we’d apply this to past social issues…
This might be splitting hairs a bit, but it basically is what happened.
Edits in italics: For US women’s suffrage they gained the right to vote in a number of cities, territories, and states then eventually gained the right to vote nationally.
Also when slaves were freed, they certainly did not become equal members of society the next day. It has however gotten significantly better over time.
If you want to push in a certain direction, you take a few steps forward, show people that the world did not burn down, and then take a few more steps forward.