cites "requests from event organisers" as being the reason.
As an event organiser I could envisage this being a very awkward position to be put in.
Imagine receieving an e-mail from someone you have never heard of, asking if they can come and take photographs at your event. This sounds a reasonable request from a commercial photographer. But do you say:
1) Yes. Only to discover that the person is in fact on the sex offenders register. Unlikely, but nevertheless a possibility.
2) No. Simple answer, but hardly the way to promote the sport.
3) Not my decision. Go talk to BOF.
Option 3 is the easy way out, and having read this thread the one which I would now take.