I think the biggest benefit of Steam sales is probably lowering piracy. Some large number of the people who got the game at 75% off would probably have just pulled it off a torrent site had that option not been available rather than pay full price.
For multiplayer games IMO the biggest benefit is a resurgence in activity. Nothing sucks more than a multiplayer game with no other players - and the natural state of all such games is that your active player base drops over time.
A sale is a good way to pump some more people into the pool. In this way I don't think sales are screwing fans at all - if anything it's extending the game's longevity.
Before steam sales and the humble bundles came along, I wasn't a paying customer.
The author's ideas about games rising in price is slightly ridiculous when placed in the perspective of an always-growing choice of games. I'm currently in the middle of a video game that was written 15 years ago. His game has to compete with that >and< everything that has been created since.
By the time a AAA title gets discounted in a Steam sale it will have been available to torrent for a long time already. A game that lasts a few days without being cracked is remarkable.
Whether there is a torrent available doesn't really factor in to the decision to buy a game on sale.
If a game is deemed "worth it" by a buyer, they are going to purchase it, instead of torrenting it. Or, rather more frequently i assume, they first torrent the game when it comes out and full price, play a bit and find it not that great. Then, when time comes for a sale, the gamer chooses to buy it and replay it, because the price is worth it.
