I have no doubt psychology goes into what’s available at what price and what’s not. Did you know nearly half of psychology studies end up being debunked over time as people’s mindset changes? The money here is made at the Crom Coin purchase time, which is before the item is purchased. As we have seen, Crom Coins go on sale, prompting stockpiling of coins. The same “scarcity” (which its not) that you describe can still he achieved thru bundles, charging full price for single items.

Time will tell, but I expect the store to change to sell much more (maybe not all as it would be in game page hell). As it stands, sales are being missed due to unavailability, and missed sales are a big deal.