Daniel Jalkut on the price of GPL:

The price of GPL is fairly obvious and easy to understand, even if there is some bickering about what constitutes “linked code.” You don’t have to be a legal expert to get the gist of it: if you want to link your software with GPL code, you must also make your software’s source code available. Specifically, you must make your software’s source code available to your customers, under a GPL-compatible license. You have to give your code away. That’s the price of GPL.

Many developers understand, and view the price of GPL as perfectly justified, while others (myself included) find it unacceptable. So what am I supposed to do? Not use any GPL source code at all in any of my proprietary products? Exactly. Because the price of GPL is too much for me, and I don’t steal source code.

Källa: The Price Of GPL | Bitsplitting.org

Exactly. GPL comes with a price and like all things (that comes with a price), sometimes it’s worth it, sometimes its not.