Interesting idea. Do you know what is the current overhead for Amazon in terms of $$$?
Considering the three companies have about 1M stuff in total, that represents ~$20B in annual recurring costs.
This effort combined with accelerating automation will lead to a much better capital:labor cost ratio (and, depending on who you ask, reduction in labor costs is massively bad for wealth equality).
About 10-25% of this is what employees pay as their part of the premium normally, the rest is employer paid. Stingier companies cover 75% of the employee cost and 50% of dependents cost.
http://www.ncsl.org/research/health/health-insurance-premium...
"According to the KFF 2016 survey, the average family coverage premium is $18,412 per year and single coverage is $6,435 per year."
https://www.groupmgmt.com/blog/post/2017/09/05/How-Group-Hea...
BTW, I think that the 19k/year is not representative of very large companies, which usually negotiate better terms. Still, your point stands.
https://kaiserfamilyfoundation.files.wordpress.com/2016/02/8...