I do think RB1 that guys who only want to pay by transfer ask this on a text or phone call, even the ones that cannot be bothered to read your profile with the mention of cash only still ask this if they are genuine because most punters that use escorts know most accept only cash and small handful now do transfers.
I have read on warnings it can be the new look n go. Excuse where many women reported some piss takers that do this as an excuse to get a cheap thrill knowing the women states on her profile it is cash only. I suppose another excuse of sorry left my cash in the car be back in 1 minute.
It's happened to me unexpectedly twice, once a new client, once a repeat booker. Both had my details from paying their deposit, the problem is phone signal at location for first can vary. He just plonked himself down on the sofa said "I'll pay remainder by bank transfer", luckily went through smoothly. The other guy said "I always pay this way", this was incorrect he paid my deposit that way but had usually paid cash for the balance.
Bank transfer is easier for me than cash due to my location, but I want it all sorted before the booking to avoid any delays, issues with apps, signal etc as well as security. Several regulars pay by transfer sending either when they make their booking, or when they confirm their booking on the day. When accepting a booking from new client I send a text containing amount to pay "cash on arrival", this wasn't in the text when I accepted the two clients who sprang it on me.