This is exactly the same thing Walmart used to do.
They would buy supply of a product from a startup supplier, who had done all the work of sourcing and designing the production of their product, and then demand ever-declining prices of said supply until the startup supplier had no choice but to abandon ship due to lack of profitability. At which point Walmart would simply re-create the supply chain themselves.
The solution is to never deal with a corporation like Amazon or Walmart, Bezos didn't get to be a pretend-astronaut wannabe by paying his bills.
The difference between Walmart and Amazon, is that Amazon can study products it had no analog for. It could decide that it wants to enter a market, study sales patterns, force a supply chain change that let them spy on it, and launch their own products from that data.
The depth of data they have is much deeper. Walmart hasn't had 3rd party sellers for as long as Amazon, and that sort of historical sales data is priceless to retailers. They don't willingly share that.
1. your product doesn't sell very well, but doesn't fail entirely. you bought yourself a job, basically, you work longer hours for the same or a little less money than you made when you were employed.
2. your product doesn't sell well enough to stay on the shelves, you've probably sunk some of your own money into a failed venture and if you have debt you're probably looking at bankruptcy.
3. your product sells well, Amazon or Walmart steal it from you.
I'd say the only way to win this game is not play. Build a product for a nice market outside of their clientele's price target that sells at a premium Amazon and Walmart shoppers are unwilling to pay.
They would buy supply of a product from a startup supplier, who had done all the work of sourcing and designing the production of their product, and then demand ever-declining prices of said supply until the startup supplier had no choice but to abandon ship due to lack of profitability. At which point Walmart would simply re-create the supply chain themselves.
The solution is to never deal with a corporation like Amazon or Walmart, Bezos didn't get to be a pretend-astronaut wannabe by paying his bills.