Lox, a cultural explanation has been put forward.
I believe it, but only because of the stature of the proposers and absence of any alternative.
Beyond that I am not qualified to defend or oppose it, and do not care anyway.
What are your qualifications for dismissing it?

Straw expressed his opinion on why they do it.
Victims may have opinions too.

Straw states as fact that this is a particular problem of BPs.
The victims state the fact that their abusers were all BPs.

In matters of fact, I believe the victims.
Why don't YOU?