This sort of thing caused games researcher Nick Yee to once call Everquest a "Virtual Skinner Box."
So What's The Problem?
Gaming has changed. It used to be that once they sold us a $50 game, they didn't particularly care how long we played. The big thing was making sure we liked it enough to buy the next one. But the industry is moving toward subscription-based games like MMO's that need the subject to keep playing--and paying--until the sun goes supernova.
Now, there's no way they can create enough exploration or story to keep you playing for thousands of hours, so they had to change the mechanics of the game, so players would instead keep doing the same actions over and over and over, whether they liked it or not. So game developers turned to Skinner's techniques.
This is a big source of controversy in the world of game design right now. Braid creator Jonathan Blow said Skinnerian game mechanics are a form of "exploitation." It's not that these games can't be fun. But they're designed to keep gamers subscribing during the periods when it's not fun, locking them into a repetitive slog using Skinner's manipulative system of carefully scheduled rewards.
Why would this work, when the "rewards" are just digital objects that don't actually exist? Well...