I see several challenges with the $50 price tag.
First, not everyone can or will buy the books online, and the LGS will have a very hard time matching the discounts that sites like Amazon can get away with. This means that the full price does still matter, and $50 is a lot to expect a random purchaser to put down on the spot as an impulse buy. The same is true for those that might only the play the game occasionally or are still on the fence about the game. For both groups, buying the books based on just the cover art might be a bit much even at a much lower price point.