It has taken me until now to realise the significance behind that. A lot of players that buy their own pots, gems and enchants complain about the higher prices - at least that is what they do when you call them out on the lack of such items in pugs.
For a large percentage of players inflation is not the rate at which a rare mount has increased in value. Rather they see inflation in terms of the prices paid for every day consumables such as pots, gems and enchants just as families view inflation as the increase in the price of food, gasoline and utility bills and not the rate of price change for business jets.
These players are of course competing with raid guilds for said items on the AH. If raid guilds were spending gold on this gear they would indeed have far less gold with which to inflate AH prices of those items. Exactly what Blizzard are hoping will happen.