I am not sure if I prefer a culture where people are expected to give away things for free all the time.
There is no such thing as a free lunch. Even if people give away things for free, they usually expect something in return. Even if it is not money, it could be higher social status, a better place in heaven, or whatever. I don't think it is a problem.
Usually on the web people prefer to give away their PRIVACY for free services. That privacy is in turn converted into advertising.
(This will all change very soon, when people are ready to start paying for a higher - and much more private and secure - level of premium service. You know, the Web will evolve to resemble the "regular' economy more and more, I believe..)
I understood the comment before me differently: I thought it was criticized that the content providers (people putting videos on YouTube) would expect something in return, not that YouTube & Co would expect a payment of sorts. I know that Social Webpages are not really free.
There is no such thing as a free lunch. Even if people give away things for free, they usually expect something in return. Even if it is not money, it could be higher social status, a better place in heaven, or whatever. I don't think it is a problem.
Gift economy: http://en.wikipedia.org/wiki/Gift_economy