It's important to realize that the real purpose of knowledge is action!
It's great to learn new/cool stuff, but why if you are not going to use and apply it. Learning is often a 'weak excuse' and it makes you feel like you are doing something. The truth is that without action you simply won't get the results that you are really after when learning it in the first place.
Information is worthless if you can't apply it and put it to use.
"The great aim of education is not knowledge but action." -Herbert Spencer
I used to struggle with this and it drove me up the wall. It's only when I started applying what I learned and what I knew that I was able to start producing some real results.
I've got a free course that I (appropriately) call A Course Of Action and it is aimed at exactly this 'knowing, but not doing' problem. You can enroll for free here:
http://www.selfimprovement-gym.com