Some time ago I was pestered by phone by one of these system salesmen and I asked him why he was selling the system rather than using it.
Presumably you guys have asked the same question?
If so, did anybody get a plausible reason?
My chap told me that his boss (the system originator) was getting out of racing having made a fortune and was going to concentrate on a creating a system for lotteries. (But obviously that's no reason for selling a system.)
The salesman still couldn't explain why he himself was flogging tripe instead of making his own fortune.

I have a fertile enough imagination but try as I might I cannot come up with an answer to that question.

What's the best excuse, sorry, reason anybody has heard?

Regards