Here's an example: here we have "journalist and author" Robert Knight at 1:41 of the excerpt from the anti-gay documentary "Light Wins" claiming, about allowing gays to join the Boy Scouts, that
"It won't just change them, it'll destroy them. It's destroyed the Boy Scouts in Canada. They're down from maybe half a million boys to 70,000 after ten years of this. 'Cause what parent in their right mind would say, `Yeah, go camping with a homosexual leader...'"
This is all complete and utter nonsense, of course. There have never ever been "half a million boys" in the Boy Scouts in Canada. The largest enrollment was 50 years ago, in 1965, when there were 288,000 boys enrolled. Since then, enrollment has dropped steeply to about 67,000. The decline in membership has been fairly constant since 1965, and there is no evidence that allowing gay scouts or scoutmasters has anything to do with it at all. Membership decline was already a concern in 2002, before the "ten years of this" that Knight claims, and is almost certainly due to a wide variety of factors, including increased urbanization.
They have to lie, because they have nothing else.