I ran across some of my Father’s WWII papers a few years ago.
When they landed in Liverpool from the SS Mauritania, they were given instructions on proper etiquette while in Britain.
One thing was to not show off your money but it was OK to sell your rations,especially cigarettes, chewing gum or candy bars, if you wanted.
Also not to complain about their coffee. The English thought we could not make a good cup of tea.
I also remember Khrushchev saying that he would have starved to death in WWII if not for SPAM.
He said either the weather or the food made him break out in boils.