I don't disagree with Bezos in his actions of helping the workers through a special charity / organization instead of straight giving them more salary. In fact, I would argue that such charity is not needed at all. However, Bezos & Amazon probably used this as a tax shield, so by giving away they actually generated more income that they would have paid the government.
I am always surprised by the number of people who complain about Jeff Bezos & Amazon while also using it frequently. I have a couple friends who actually only support local stores, and I think they are the only ones who truly believe that Amazon should not be a monopoly. The way to de-monopoly a company, or to make someone poorer, is to not use the products, not giving it assets by using it, and only speaking about it. The reason why Jeff Bezos & Amazon is so rich is because the general population using them, not because of anything else.
In terms of the workers, I do believe this is a free market of hiring. In fact, if not for the minimum wage law, there are probably many unemployed people wanting to work for Amazon, and other companies, at an even lower rate. In addition, these workers can always leave. Free market determins that if enough workers leave, Amazon would have to raise wages to attract employees. However, the current market is very obvious that there are more employees than employers out in this world, and therefore it makes no sense to raise wages purely for the sake the existing employees. Even if Amazon, and other large corporations, raises wages, its wage bill is still the same. The difference is less people get it. Before, $100 of wage budget was shared among 8 employees, after the raise, $100 of wage budget is not going to change because they can't drive up the cost without driving up the price, $100 would be shared among 5 employees, effectively laying off 5 employees.
In addition to using Amazon frequently, all the doubters forget that there is a reason why Amazon is so popular. As harsh as it sounds, the low prices is driven by the low costs, a large part the workers. So I still rest my same case, if people complain about Amazon, don't use it. If enough people stop using it, they will need to act. But for now, it seems like the majority of the population is happy with Amazon's benefits of low price and convenient, and therefore has no rights to complain the attachments of those benefits.