Corporations and other large moneyed interests want to control as much as they can. Their goal is to maximize profit and not watch out for the rights of regular folks unless it makes them more money. (That's just the nature of the beast, although every now and then there are exceptions like Ben and Jerry's.)
Luckily there are some brave souls who stand up for their rights and in so doing protecting those rights for the rest of us. People like Stephanie Lenz. Universal Music was a bully and forced YouTube to take down a short 29 second baby video just because it happened to include a snippet of Prince's "Let's Go Crazy".
Universal Music should have applied a reasonableness test to this before making the request. Likewise, Google and YouTube should have used better common sense in reviewing the situation before taking the content down as well. But it is usually cheaper and easier to stick it to the little people rather than push back on other corporations. Money talks.
Thankfully EFF (whom I support) stepped into help Stephanie and they have taken the fight back to Universal Music. Hopefully this will make corporations more careful about respecting the rights of others rather than trampling them willy-nilly.
For more information on Stephanie's case, please see:
Basically corporations will do whatever they can get away with, even if it is not right or legal.
For more information on EFF and their work to protect free speech from copyright and trademark abuses, please see: