Jailbreaking has become a fashion more then a need and everyone waits for it to come as soon as the new iOS version is announced. When you ask someone why they need it, most of them answer either to get paid apps for free or to bypass Apple's UI restrictions. Some people even want it for software unlocks but solutions like this have led to some decrease in their demand.
The guys over at TheJailbreakShop have compiled the data and released an interesting infographic to reveal the info. The cost they ask for Jailbreak makes them look shady but this one surely is worth a look.