When returning from an overseas tour with the RAF in the 1960s it was
quite common to find that the final pay parade prior to returning to the
UK resulted in a handful of notes from the British Linen Bank, the
Clydesdale Bank and sundry other obscure but perfectly legal outfits.
The buffet bar on Swindon station (first port of call after RAF Lyneham)
was remarkably knowledgeable in such financial matters.
Bruce

Similarly, I work in one of the main offices of a bank with head
offices in England and Scotland, and the canteen are used to getting
Scottish notes from visiting dignitaries who've come down from Glasgow
for the day- they just keep them to one side for the bank to clear
internally. The opposite effect was noted a couple of years ago on an
Inverness-Kings Cross HST south of Newcastle, where (it being a
Sunday) the only notes in the float on the catering trolley were
Scottish.