I don't think this is necessarily exclusive to Amazon or even big box retailers. I did temp administrative work for a defense contractor and had to sign a non-compete document, even though all I was doing was organizing calendars and ordering catering.
They just wanted to make sure I didn't take any notes on any blueprints and went running to a different DoD contractor. It didn't mean I couldn't transfer my MS Outlook knowledge from job to job.
But you don't need a non-compete for that, just an NDA.