iCloud has little to do with iTunes on your computer.
It's a direct service to your iOS device, and in many ways it is meant to replace the iTunes program on the computer for those that don't want it, or don't need everything that program can do. If you still want things to work with iTunes, you can, but you will have to use the cable (or new wireless syncing) as usual.
The stuff you are seeing show up is probably one of the few links between iCloud and iTunes. If you go into iTunes Preferences > Store, you will see that you can turn iBooks, Music, and Apps to automatically download there when they are purchased on other iOS devices. If you want that to work the other way around go to Settings > Store on the iPad and turn the same services on.