Yeah, I’ve seen a lot of it for two things.
First being sqlserver, though that’s been able to run on linux for a long time now, there’s a bunch of features not supported but not a deal breaker for a lot of people, I haven’t encountered ssis or ssas in years for example.
Second being Internet Information Services (IIS), which some people really seem to like.
Wouldn’t be surprised if active directory required a windows machine either, definitely a bunch of cases I’m not considering or aware of but I’m no sysadmin.











And even for fresh water, you have biofouling to worry about and what to do with the water after you’ve used it, can’t just dump it into the environment untreated.