While it may be true that some collectors don't use some or all of their knives, "super-expensive" is relative and we are nowhere near the top of the spectrum here with a $200ish large-production Spyderco. Mid-tech knives (partially handmade) run from $250 to $750, 'custom' (totally handmade) knives range from about $500 to $3500ish, and above that most people would consider them 'art knives' - which are, almost by definition, exactly what you're describing. You have to get past the custom world of hand-shaped zirconium bolsters, timascus clips, rose gold hardware, and custom engraving before you get into the $5000 art knives with precious metals, gemstones, unobtanium, etc.
And, while your statement could easily be true for some people and some knives, Bohler designed Elmax steel for hard use and I expect most buyers who are attracted to this knife plan to do some work with them. It has to be keep cool during grinding to retain it's hardness attained in the heat treatment process, and it's an absolute monster to sharpen - but if you have the time and some good stones, it will stay sharp through a lot more abuse than almost any other commercially available steel; ZDP-189, 20CV, S110V, M390 and some others come close, but Elmax has earned a pretty solid place near the top of the pile.
All that being said, I think what you're getting at here is a very interesting question: "What's the most you would spend on a knife that you will actually use?" When I first started, that number was $50 for me. Then it became $100, then $150. Now I carry and use $500+ knives. I'm not sure I will ever cross $1000, but I said that about $150 two years ago, so...yeah. The rabbit hole is deep, it's hard to see how far you can fall until you're halfway down. As evidence, I point to the name of a favorite IG account: "@TodaysGrailTomorrowsBeater" - pretty much sums it up.
Anyways - you're not wrong. But there are plenty of people who wouldn't think twice about beating the crap out of this knife - in fact, they might be buying an Elmax blade precisely for this reason. Just sayin: to be "super-expensive" in the knife world requires at least one more "0" in the price and maybe two. It's all relative, I suppose.