The more important factor is competition. If Amazon hires 10 people, you can bet tradition retail needed at least 11 to do the same amount of work. If Amazon is undercutting them, those businesses will die off, and 11 people will be out of work.
If Amazon wants to hire 100,000 logistics/fulfillment employees, you can bet there's more than 100,000 people who will be out of work elsewhere.
Bias note: I spent 5 years making software for Amazon's logistics division.
That's the actually important question. If Amazon is convincing people that delivery service is worth paying a premium for, that's a new product/service that the economy is producing and employing people for, and is itself economic growth. If Amazon is instead more efficient and competing on price, then they're only freeing up the ability for the displaced to do productive economic work elsewhere in the economy.
That is exactly what they do in the UK. Deliveries are outsourced to other companies (but still under the Amazon Delivery Network brand). Those companies then hire people as contractors, pay them close to minimum wage, but use every trick possible to ensure they see as little of that as possible (i.e. pay reductions when aggressive delivery targets are not met, charging extortionate rates for vehicle hire and insurance).
http://www.bbc.co.uk/mediacentre/latestnews/2016/amazon-insi...
Or under minimum wage: Amazon Mechanical Turk [1]. Which is below the minimum wage of a lot of countries (at the very least the entire Western world as we know it) [2].
[1] https://en.wikipedia.org/wiki/Amazon_Mechanical_Turk
[2] https://en.wikipedia.org/wiki/List_of_minimum_wages_by_count...
That doesn't sound like contract work to me.
headline can also be "Amazon plans to hire 100,000 below minimum wage workers in light of relaxed labor laws"
Not saying it couldn't be better, or the timing isn't suspect in regards to maximizing PR, but don't forget the humans this will positively impact.