Everybody is exerting "force" on everyone else, sometimes indirectly. The contract between Amazon and the laborer was signed under the duress of threatened homelessness / lack of healthcare / starvation. Amazon signed the contract under duress because it needs people to ship its boxes. Amazon is not special and neither is the worker.

Any deal we make must exert force on someone (a restatement of "the world isn't perfect" within our framework). So who should be favored? Put quantitatively, there's a scale between the minimum price at which a person will sell their labor and the maximum price Amazon can pay for the labor and still turn a profit -- where should the actual price lie? Market economics looks to supply/demand balance for unskilled labor and slides the "final price" all the way over to the minimum. A libertarian would claim that this is just (both parties "consented") and reject attempts by the government to meddle on the grounds that the market knows best. A philosophy that rejects the notion that both parties "consented" (both were under duress) opens the door to policy adjustments that push prices away from one extreme end of the spectrum, because it sees these as less just. Since Amazon has all the power under the current system, such policy adjustments would favor the worker.

I would prefer that this be implemented IRL using a basic income or negative income tax scheme (ameliorate (!=eliminate) the source of labor's duress at the source) rather than by implementing a minimum wage, but that's beside the point.