I agree that you need to make the right decision depending on what scale you are at. The reality is that most companies are at the scale of a small shop, and it would be better (total cost of ownership) to use Amazon's highly automated services.

However, every sysadmin I've met (and I used to be one) would like to think they are managing Walmart's trucking fleet, when the reality is they are more like Joe's local furniture delivery.