I've been giving this subject a lot of thought the last day or two.
One thing that protects me from this sort of thing is I'm chronically unsociable and suspicious - the sort of person who doesn't answer the phone unless the caller is on my contacts and doesn't open the door if the doorbell rings if I wasn't expecting a visitor.
A Chris Beek would literally never get the chance to speak to me, let alone ensnare me.
It has its downsides - networking can be a big edge in betting, as Slim rightly says in his list, and I literally let someone else do it for me.
He's actually at Kempton Park as I write and in our deeply transactional collaboration/friendship I do a lot of the analytical digging while the lazy - but gregarious! - fecker gets out there and actually finds things out, which he feeds back to Mr Geeky Loner here as part of the deal.