It used to be that expansion packs actually added something new and exciting to a game. These expansion packs were like getting a new game at a discounted price. Life was grand for gamers.
Then along came the Sims. The expansion packs, while a little cheaper didn't add a lot. This model was soon adopted, due to the success in the market place. While some gamers rejoiced, others were concerned about the path that was being followed. In essence the innovation and features were dropped in favor of the much cheaper content development model.
We live in a world with half finished expensive games that require another $20-$80 to get a complete game. Not only is this easier for studios (they don't need to hire/pay a content team) it gives them more money on less investment. A better ROI if you will. Just at the expense of their fans.
As companies look to increase their profits eventually someone is going to look at old school arcade games. Those games were great at monetizing users, by making you have to pay not only for content but per life. I can see a point soon where gamers will have to pay per life. It is already happening in these freemium games. All it needs is a little more time.