Wow, what a great thread. I wanted to chime in as I bought a set a few months ago.
When buying hi-end anything don't even try to justify the cost. Is a Bugatti Chiron worth a list price of $3m? Is a Salvator Mundi worth $400m?? And is a house in Beverly Hills worth $100m??
The answer to these questions is 'maybe'. If you can afford it and it brings pleasure to you then it's worth it. If it brings you no pleasure then it's not.
As for the why are they so expensive, it's simple economics. Companies like Grimm/Ferrari/Patek Philipp etc do not mass produce product. They need to have very high margins to make money. Their production costs are very high as everything is hand made and not just run through a line in China. There is NOTHING cheap about these speakers, every single part is very well built. It looks expensive, it feels expensive, it's clearly well made.
The Grimm's have spectacular sound and as much as I wanted Kii's an A/B test just didn't hold up. The Grimm's were better. But the Grimm's were better to me and the music I like. They may not sound better to you, so just buy what you love and what you can afford.
Are the Grimm's 3x better than the Genelec's? That's for you to decide. Listen to them side by side and see. The PMC MB3's are $90k, are they worth 3x more than the Grimm's? Beats me, I have never heard them. The subject of worth and value is very subjective.
I also use these for work so I needed something very accurate and the design works perfectly for my set up. I got the higher studio version. Well actually that's all BS- I just wanted some really nice speakers and used work as an excuse
When I first got them I was not blown away immediately but after about a week my ears got acclimatized and I was so astounded. I couldn't care less about any stat, spec or what anyone thinks, some songs make the hairs on my arms stand up and other you can just 'feel' the emotion in the song. I have sat on the couch, in front of the speakers with my girlfriend and listened to a solid hour of songs. Some of the songs she can't hold back the tears- these are emotional speakers. Even though they are ultra clean they are still able to invoke a strong sense of emotion.
Sometimes these speakers will startle me with a thunderous cymbal or make make me laugh at how detailed they are. I can hear fingers coming off the strings in a bass guitar or hear the gentle tapping of the hammer on a piano. It's pretty wild, the more you listen the more you hear.
When using them for work and mixing I get the the most accurate detailed sound that let's me set the right mix and effect for each track. They are versatile.
The customer service from Grimm is BEYOND incredible. When I got them, Eelco Grimm sent me a message as he wanted to make sure I had them set up correctly and the room was properly treated. The packaging on these was also amazing but I found a very small scratch on the bottom of the main speaker. You wouldn't be able to see it unless you looked underneath and had light on it. It was a light scratch in the paint maybe 2mm long. Eelco told me to send it back for repair at his expense. I didn't bother because it's so tiny and he sent me $500 to get it fixed locally. Just an amazing experience all around.
Bottom line is nobody can say whether these are worth $30k or not. It's your money so you will have to decide for yourself but in the high end audio world there are many more expensive speakers than these that to my ears do not sound as good.