Kindle Fire is based on AOSP, that was my mistake. I will say Amazon is a rare OEM in this regard; they're tablet-only, and happy with AOSP because they have their own app store that don't need Play Services integration.
For instance some parking meters / train ticketing machines / payment terminals run Android. source: I work for company that makes some of them though we are moving away from Android to more classical embedded Linux.
Google play services doesn't matter in these contexts.