that's not a lot of money. you get to use the case again and again, as long as you keep with a mini-itx format, you can upgrade for years and still use the same case. to me, there's value in that.
plus, silence is golden ;) if you have never used a 100% silent pc, you have no idea what you are missing. even the smallest whirring fan can be heard in a quiet room.
recently, I was cleaning up my garage and I found all the pci cards (etc) that I bought over the years. I found my first 'high end' pci card, an s3-968 4meg video card that I paid over $400 for, nearly 20 years ago. we forget that computers used to cost a LOT! now, they are mostly dirt cheap. $200 for a case that will let me watch movies and listen to music in full peace and quiet is easily worth 'half of that video card' that I bought so many years ago.
even going back just 10 years, the famous lian li cases were well over $100 for the aluminum mid tower and that did not include the $50-$100 you'd pay for a good psu.
today, on that fanless system, the psu fits inside the atx power socket and is just a small board (pico-psu) and those can be gotton for under $50.
gig-e: onboard. video: onboard. disk i/o: onboard. sound: onboard. just need a mobo, disk, mem and cpu.
when I look back at where we've been the past 20 or so years, I really don't mind the very low prices we now pay for very fast computer hardware. the case is on the pricey side, but its not outrageous, really, and there is solid value in removing all noise from the computer.