Other than the most obvious reason – any app/game that you want for free – rooting has many benefits.
Rooting your Android gives you the freedom to customize your phone in any way that you want. You can run a clean version of android which will drastically improve the performance of your Android device.
You will always be able to run the latest version of Android. Rooting also leads to better battery performance. You will be in total control of your Android!
Free payed apps, better performance, better battery life, unlimited customization!
Rooting really is a no-brainer!