Well I'm sure most people who aren't stupid or financially reckless could live off the money we give the royals, by employing savvy financial advisers and investing wisely. I wouldn't say that's really earning it though, just as a lottery winner who invests wisely isn't really working to earn it. I'd class that as sponging.
Also, Charles isn't a "powerful force". He's outspoken and often embarrassing, much like his father.
the £14m private income is from his own business, and from the looks of that he contributes £1.3m to the country.