“Withnail and I” bona fide … ?

In “Withnail and I” the lads are in the country and the farmers won’t sell them any food. Withnail (or is it I), says, “We’re not from London. We’re bona fide.” What does that mean? During the 1960’s did people from the country REALLY hate Londoners? If so, why? Are what are they bona fide about?

It’s just them saying “we’re not arrogant city types, we’re genuine rural folk”. Some people in the countryside often hate city folk even today – e.g. some of the attitudes expressed during hunting debates in the UK recently.