The replayability of games

Today during my english class, i zoned out as i usually do. Today my mind wandering to a topic that i had been thinking about earlier: how replayable certain ames being released are. Fallout 3 and Oblivion are two obvious examples of such games. Open world games where you create your own character, these are incredibly replayable for the simple fact that many things can happen differently every time. Dragon Age Origins is another favourite of mine which is rapidly reaching 150 hours played on my third playthrough. This is most likely much higher than most peoples time spent in the game, however, this leads me to my next point. We all have those games that we will play constantly over and over again simply because we love it, where other people may think differently. An example for me would be the Skate. Franchise. I currently sit at near 50 hours played in Skate 2, and nearly 60 played in Skate 3. I am more inclined to play these types of games because i am a skateboarder in real life. We all have influences to our game decisions and which games we will spend the most time in. 
I sometimes wonder if the amount of replayability in games could have an adverse effect on the games industry though. Because i have spent so much time in these games, i am far less inclined to go out and purchase one of the newer games that peaks my interest. If games continue to increase the amount of replayability in them, good it have a significant affect on the rest of the games industry?
If you have any input or would like to share some games that you've spent a large amount of time in that others may not have, feel free to reply :)