They don't do that to ~25%(!!!!) of customers. You can't continuously run an above the table business involving card processors if even 1/10th of those people do a charge-back.
That 22% is a lifetime figure, not a per-occurrence figure. I've had my credit card info stolen several times, yet the fraud rate per transaction is way below 1%.
with an average number of escort per client at 26, and at least some of them being repeat customers (but possibly some of them being robbed multiple times), it doesn't look that much... Well below 1% per act.