You've created a straw-man so big it's trying for the basketball team.
As arron said, the relation between you and the brand can and should be moderated by you. Furthermore, just because a monetary transaction is involved doesn't mean it's a free market at all. Facebook is the faceless bureaucracy you rant against when it's trying to gate brand communications like this.
So Facebook can't run it's own business? Facebook charging for "reach" is the essence of the free market. They have developed something valuable and now they are going to sell it.
And no, it isn't a straw man. Users suck at moderating and curating. If curating a Facebook presence becomes a great deal of work, users won't do it and will just stop using the service.
Some of the comments above also make the point that "Like" is terrible UX, it doesn't communicate what it should.
As arron said, the relation between you and the brand can and should be moderated by you. Furthermore, just because a monetary transaction is involved doesn't mean it's a free market at all. Facebook is the faceless bureaucracy you rant against when it's trying to gate brand communications like this.