On Tuesday, 14 November 2017 00:56:43 UTC, wrote:
Was at a show of some kind and the merchant could no get a cellular
signal for his electronic terminal so brought the old machine out.
I didn't realise they could still do this and judging by in similar
circumstances the number of traders who put up a "Sorry Cash" only
notice a lot of traders either don't either or there are hoops and
risks to go through to retain it which many don't want to be involved
with.

If a transaction is chip and pin verified the trader has almost no risk the trasaction will be reversed. For manual imprint transactions the trader carries a large risk and is also supposed to obtain telephone authorisation for anything over the 'floor limit'.

Owain