Wash sales, long term/short term gains and associated tax issues, RSU withholding which is a fixed amount and not based on the income tax withholding, and a typical broker account to sell/get money are massively more complicated than a direct deposit to your bank account and money back from the government at the end of the year unless you massively screw it up.

By number, most of Amazon’s employees are working minimum wage and probably don’t have much of a balance. Many of them might get evicted if pay gets delayed even a couple weeks.