Not too long ago I met a local sportive coming the other way whilst on a cx bike. Bastards ALL greeted me. After returning the first 30 or so I realised there was only one thing for it and put my head down and pretended to be laying down some awesome power and gurning too heavily to acknowledge them.
Another anecdote – did the Lemming trail ride a few years back – beautiful weather and passed hundreds of other mtber’s coming the other way. I greeted most if not all, about half returned it.
What does this prove? Nothing. people draw their own conclusions based on their personal experiences but coloured heavily by preconceptions and prejudices.
I think this need to be acknowledged as being part of a tribe is unique to the UK – certainly in South Africa and Europe you don’t get it as far as I have seen.