No, but we are part of the system of information dissemination which allows consumers to make better decisions. Something from Brick Lane Bikes might seem fairly priced to a cycling noob, because he has too little information. Obviously, this market segment can be profitable in the short term for somebody who has no interest in repeat business, but the interests of sellers who exploit poorly informed buyers are not those of this community, one of whose purposes is to enable consumers to obtain maximal value by sharing information about good products and good offers.
To suggest that Brick Lane Bike's pricing is 'fair' just because they are making some sales is also missing the point somewhat if you believe in free markets. The question should be, what would be the selling price for Brick Lane Bikes if all buyers had perfect market information?
ftfy mdcc ;)