Apparently this was conceived as a market segmentation scheme: people outfitting servers could get ECC when they pay a huge premium. They would thereby not be tempted to cheap out and buy consumer-grade equipment, otherwise wholly adequate to meet all their needs at a radically cheaper price.
That we cannot get laptops or even desk machines with ECC, and so have them crash frequently, is seen as a trivial side effect of the strategy. If you did not hate Intel enough before, you may increase your hatred accordingly. Intel doesn't hate you back; they simply care not even a little how you feel.
(Historically, just running Microsoft software was overwhelmingly more likely to be the cause of a crash than a memory bit-flip; and there were orders of magnitude fewer RAM bits at risk. Microsoft succeeded in getting customers to accept and even expect frequent crashes; before MS, a program crashing was grounds for a refund.)