If you could be construed in any way to be a competitor of Amazon (retail namely), you'd be crazy to pick Amazon, who is in the business of stealing their customer's lunch money at every level.

You'll be surprised to learn that quite a lot of major companies running on Azure aren't Microsoft/.Net shops. Linux/Java workloads are very common. The tooling is pretty good for all that stuff too (nearing "First Class Citizen", but mayybe not quite).