I've been saying this for years but just read an article about production companies that scour youtube for videos they think could go viral. They then offer to buy the video from the person who posted it for anywhere from $250-2500. They then start their marketing magic. Posting it all over facebook, twitter and shit, getting it on the news and all of a sudden this little video with 15 views has a few million and these companies make $10's of thousands of dollars from the views and advertising hits. If they find people with good personalities they offer to produce more shows for them. You think they're just homemade videos but it turns out they have production people behind them.
So if you ever wondered how that video you saw of a guy getting kicked in the nuts by a goat has 10 million views. Now you know.