There's degrees here, and Amazon treats vulnerable people with a very high degree of hostility and abuse. That fact alone tells me everything I need to know about the people running that organization. They're not about mutual benefit - the real reason for capitalism - they're about exploitation, and they'll do it to anyone and everyone they can as long as they can get away with it.
Besides, you ever bought computer part, chip, etc. that was made entirely ethically in a first-world country paying good wages to skilled labor with rights, benefits, pensions, healthcare and so on, where the company and all its officers were entirely free of moral flaws? No you haven't, you know why? Because there aren't any and there never have been.
So compounding your error in logic here is the inescapable fact that no alternatives exist, which just further demonstrates the impotence of your combative argument and intent.
That's not all, though. It's only a matter of time (how long? that's up for debate) until antitrust - be it real action, or merely the rumored specter thereof - results in some degree of upheaval internally. While I admit this is purely theoretical at the moment, it's certainly not outside the realm of reason to have concerns that said equity may wind up severely reduced in value if you get screwed by the timing of getting that equity vs. antitrust related events.
If I were in your shoes, unless I had no job at all and was desperate for the very first thing that came along, I'd give Amazon a hard pass for every possible role, bar none.