There's been some adverse comment following the news that people chosen to carry the Olympic flame around Britain have sold their torches on eBay. Those who have spoken to the media have defended their actions by saying that they only did so in order to raise money for charity.
It seems that not only does doing something for charity let you off the hook but that doing something not for charity is now seen as suspect. Take the London marathon. It started thirty or so years ago as a sports event. It is now a fundraising event. TV reporters stopping runners now routinely ask them "who are you running for?" At this year's event, one guy replied "for myself, just for fun" and was swiftly dismissed.
It reminds me of the story Doc tells in Cannery Row by John Steinbeck about how as a student he walked from Chicago to Florida just to see the country. Along the way, he told people what he was doing. They were suspicious and unwelcoming until he lied and said he was doing it for a bet at which point they invited him in for a meal.
I'm not saying that people shouldn't do things for charity if they want, just that they shouldn't feel that they have to either.