Why do social networking sites require funding since most of the sites rely upon the public for their content?

I'm intrested in why social networking sites require so much money if all they are doing is providing a forum for other individuals to add "their own" content.

Why do social networking sites require funding since most of the sites rely upon the public for their content?
for youtube they need the money to buy computers to process everything. also they need profit. people are so greedy!!!
Reply:to get rich..





server costs, programming, design..all costs £$£$£$£$£
Reply:That forum is not free it is monstrously expensive: power, bandwidth, litterally a team of professionals keeping it running. I heard an report on the radio that stated that before it was bought by google you tube the bandwidth bill alone was in the millions... per month.