I must be completely ignorant, as I say hello to far more ramblers when I'm out riding on the hills than I do to other people on bikes when I'm riding on the road. Is the OP sure none of them raised a little finger to acknowledge his presence (as is standard for acknowledging other people on the road)?
Though I actually recommend he does do what he was originally thinking of and register on their forum to post abuse. Could you just let us know first what club it is, so we can watch - should be amusing? Not that either of the roadie clubs I've belonged to has a forum on their websites last time I checked.
Then I realised I was in my roadie tribal colours and chased him on foot to aplologies but it was to late, he'd gone. Am I a bad person? 
