Speaking as a one-time bank teller (or cashier as we called it in the UK) I can make an observation or two.

Hating irrelevant chat is just as common on the staff side of the screen as on the public, and shaking off the over-communicative customer so that you can get on with the people who actually want service, without offending the talker, is quite an art. It is all a matter of balance.

So yes to silent orders, a great idea, hairdressers, bank personnel, taxi-drivers, window-cleaners, all good but above all, customers.