"Why did they not just show the cheaper rate from the initial rate screen, not once you were down in some obscure web page?"

This situation also prevails with "Weekend Websavers". I have mixed feelings about it. On the one hand, they are trying to attract business with an incentive. Giving that incentive automatically to everyone defeats the purpose in every case where the individual booking would have been none the wiser and willing to book at the going rate. That's a free rider. On the other hand, "Best Available" rate should seem to mean just that. (This explains why it is actually: "Best Available.**". Ever wonder why you can go through the entire booking process and never find out what those two asterisks are for?) I can see why you're annoyed, but I'm not sure that it should color your judgement going forward. If the value is there, you should leave this unfortunate incident behind and choose based on your best interests.