This will be a very unpopular post, but I can see their side to this - I will explain.

Forget it's Sony for a moment taking a cut of the profits, forget Microsoft in the case of the Xbox or even Nintendo with their underpowered piles of antique crud.
In fact, it's debatable just how much if anything Sony earn through the software (games) sales anyway.

For this, maybe don't blame the manufacturer - blame GAME store.

The store GAME as it's trading model, sells used and new games, they also trade in games, at a truly rubbish price.
However for their turnover, they rely greatly on selling mainly used games, at a price often of just a couple of pound below the price of a brand new game.

Even anyone going into GAME an attempting to buy a brand new game, if they had it in stock second hand, the assistants are trained to try sell this game, with the line "you can get it cheaper this way".
Now picture - a brand new release, it gets traded in pretty quickly - this will always happen. The new one will be there for £45, they will try to sell the second hand one at £42, which they accepted as a trade for probably £30 at the very most, most likely less.
Makes business sense for them.

HOWEVER, then we have the flip side. The game developer gets mediocre sales, that new game on paper has hardly sold any. Their profit is cut drastically, the people working for them don't get their bonus's - and these are just normal people doing their job.
There is less incentive to produce new innovative games (Many gamers have been complaining for years that all games seem the same now, this is no accident, the set up costs of producing a new game are huge, and it just isn't worth the risk of not recovering this cost -hence yawn again Call of Duty 132 or whatever).

The only places at the moment which dare to produce risk taking games, are online places catering to facebook.

Now, if this second hand trade could be cut right down - well it's going to hit GAME's profit, but they nearly went to the wall anyway, hmmm.
What it will do, is increase the takings greatly of the video game manufacturers, and they will be able once again to produce more quality games..................at least that is the idea.

The down side, is of course - will they make them affordable more? At the moment they release them at a high price initially hoping they can get most of their costs back before the second hand market kicks in. They might decide to keep it high and stick at that, or might still reduce the costs for an older game to keep the sales happening.

Will people be prepared to take the risk of buying a game, knowing they won't be able to sell it on? A big drawback and one that concerns many.

Very difficult one to call. It should result in many more quality and different games, it should result in a price fall in games, but may upset many as if they buy a duff game, they are stuck with it.

What is sure, is that the other manufacturers will be doing the same. The next Xbox will also have this protection. Of course, it will likely be hacked, just as Xbox hacks aren't exactly hard to come by.