Working with, not for. AWS has their own consulting wing, and they can’t possibly take on all the business themselves. It is a mutually beneficial relationship.
I think they are just emulating the successful Microsoft VAR model that had different tiers from Microsoft Certified Professional to Microsoft Certified Systems Engineer to Microsoft Gold partners. Microsoft probably just imitated Novell and Cisco. The business model works. I don’t think Cloud adoption would be anywhere near as high without corporate-approved partner designations with multiple tiers.