A few years ago, I worked on a video game published by Microsoft. We ran game servers in Azure, and on Windows for obvious reasons. The project had to pay for the windows licenses from MS, despite being entirely funded by them, partially developed by an internal studio, on aMS first party IP.
I don't recall how much it cost exactly, but the cost of the per-core windows server license hourly is not far off the cost of a core on AWS these days.