It's not greed. It's markets, basic business and common sense.
Or are you suggesting that if, for example, you are selling a rare car and have several interested active buyers, you're going to sell for the lowest price that breaks even? Of course not. You'll sell for the best price you think you can get.
Economics 101 - if demand is high and supply limited or fixed, price goes up. (*note)
Business 101 - company bosses arrn't there to sell limited stock in a limited production capability at minimum price. They owe a statutiry duty to operate in the best interests of the company investors/ owners. They aren't social enterprises for gamers.
And bear in mind, without those investors putting miney in, up front, and taking a risk, these cards wouldn't get developed in the first place. And don't imagine the risks aren't real. I remember talking to one oc ths founders of a very well known hard drive msnufacturer some years ago, who pointed out, "get the capacity point for next release drives wrong once, you make no money that year. Do it twice on the trot and you're bankrupt".
As for prices dropping 10%, well, we'll see. If that tempts enough consumers to buy, it'll probably stick. But if enough think they're still overpriced and hold off, prices will drop further.
The laws of supply and demand cut both ways - demand>supply => prices up, but equally, supply>demand => prices falling. Card companies coined it on the way up but IF consumers hold tight, it'll bite 'em in the ass on the way down. And that is also basic economics and market forces. Factor in a large number of angry consumers feeling ripped off and prices could fall quite a bit .... which companies ought to have taken into account in the "best interests of investors" stage.
*Note - There are other issues, like price-elasticity of demand, and granularity of market structure, but that's more like Economics 201 than 101.