Those two subreddits are really a work of mass psychology. I liked your comparison of them very much. Perhaps it would be interesting to add that /btc and /bitcoin also do a great job at blurring the lines between corporate interest and ideology. Ask the average member of either group and they will they you what 'evil companies' support the opposite band, and then they will tell you how and why their Bitcoin is the true Bitcoin.
And then you have the problem with actual trademark for "Bitcoin", and laws get involved and the knot continues to grow bigger. So much for "consensus".