Censorship has always been around. How many of the books once banned by the US have you read?: http://en.wikipedia.org/wiki/List_of_books_banned_by_governm...
How many of the wikileaks cables have you read?
99% of The Pirate Bay is people downloading entertainment. Sometimes it's entertainment not available yet in their region. Sometimes it's a show on cable that aired last night. Reducing the friction for consumers to get content is a business problem. The Pirate Bay thrives because big media fails to solve that problem.
But 1% of the time - maybe less, The Pirate Bay links to content that will have no other home. Where powerful people can't squash it. If we have no place outside the reach of national governments where things that make them uncomfortable have a chance to spread, then we have no freedom.
So, while The Pirate Bay is the seedy underbelly of copyright infringement on the internet, it also gives you freedom. We need to protect that.