This conversation looks an aweful lot like the anti-Walmart and anti-Starbucks movements. When a business starts to become massively successful such that they start to kill small business - people start worrying about 'the community'.
Change is hard. No doubt this is just the beginning. Amazon is going to get a lot bigger. It is not too hard to see anti-trust charges in the not too distent future.
Food for thought: people like to talk about what Facebook's database is worth but Amazon has my online purchase history going back 10+ years. I know which data I would rather own.