I haven't met any of those people, I'm amazed that they exist.

I wouldn't expect anybody to write a commercial scale program in asm, but inline asm is still of value in games for creating specific high-speed routines.

However, I think the why doesn't have anything to do with which tool is best, rather I would expect that it has to do with the challenge and a desire to try new things. I got into programming because I was doing some mindless work (stepping on alligators in the Everglades, but even that gets old eventually), and wanted something to think about. I found assembler to be simple and straightforward for small things, but nothing that I'd want to use for a whole project. Still, knowing it can sure help in C.