Government buy it? Why? Is there some compelling reason that Facebook needs to exist? It's not like a loss of Facebook would cause massive unemployment or be a giant hit to the economy. (Hell, losing Facebook might actually lead to productivity GAINS for the economy overall.)
Better to have the government pass a law that says "you know those licenses you click on that say 'we can change the terms any time we feel like it'? Yeah - those are invalid. Stop doing it or you open yourself up to a lawsuit. You need to give your customers 90 days notice of changes to your privacy terms and conditions, you need to actually send them via a paper trail (to make the company actually have to expend some money to change their minds about something), and you need to provide a bullet-pointed summary of everything you intend to sell, everything you intend to make public and everything you intend to keep private every time you do this in addition to the legalese that you provide. When you do that, you need to provide a simple way for customers to decide to leave your system and you need to delete all of their personal data on your servers immediately at their request. And if you fail to do these things, the FTC has authority to prosecute you for criminal fraud - in addition to the civil lawsuits your customers will be able to file against you."
There are many other ways to go about it, but the key ingredients are that customers should always be notified of what information the company is going to be selling or providing public access to, how they can terminate their accounts if they object, and give them a period of time between when the changes are announced and when they are implemented to get their account removed from the system if they choose. Those are the kinds of things that companies should be doing anyway, but without a law on the books there's no incentive for them to do so.