For this argument to make sense, you would first have to show that in the absence of Amazon, low-skilled labor on aggregate (including the people currently work

For this argument to make sense, you would first have to show that in the absence of Amazon, low-skilled labor on aggregate (including the people currently working there) would be making more than they currently are making. If it turns out that they would be making less, then it's not a coherent argument because it means that Amazon's presence has caused welfare costs to go down. An example. Suppose someone is working at the best job they could find for $8/hour, and I decide to hire them for $15/hour. Am I "dumping the cost onto society"? Maybe you could frame it that way, but in reality my contribution has been to reduce the burden on society by $7/hour.