Except amazon would immediately take the other side of the bet, and then manipulate the market.
I came here to reply this. They would play the system if it ever had enough people betting.
Taken to it's furthest, people would be running delivery vans off the road and calling in bomb threats to package hubs
You're right they will have more responsibility to pay for losses out of their wage.
Welcome to late stage capitalism, your next pay review is in 12 months.
We'd have to get around the gambling aspect of it and call it insurance
Oh, wait, insurance is already legal gambling, where the house always wins