Could they sell a high-end amp without the fancy

I think there's the false assumption that using lesser quality metal work will result in a dramatic lowering of the sale price. If a manufacturer went this root, would a $10k amp suddenly cost only $6k? I think not!

A high powered class A or A/B amp will necessarily be on the large and heavy side. Couple this with the fact that vibration and resonance control become increasingly more important factors as the quality of equipment improves and the high end amp manufacturer has little choice but to go with substantial metalwork. Once you're stuck with a big piece of metal to begin with the laser etching or mirror polishing doesn't add that much incremental cost.

+1 to what Unsound said. There are manufacturers out there that spend more on the innards than the outtards per se. However, if it's not in an impressive looking case, will the audio journals give it their highest ratings.....doubtful. Most want to pay for the jewlery/name. If you don't, you can find small manufacturers that don't play the game, like PBN, Bear Labs, Music Reference, Quicksilver, TRL, CODA, etc.

That's the beauty of DIY. You can make it as bling-infested or as utilitarian as you desire. Spending more on the components than the casework should result in better sound and a heavier wallet. Hell, if you're only making one, you can even spend 6 months on the casework to make it a masterpiece, for no more cost than that of your spare time.

I agree with Peter S. Music reference makes great stuff without the bling factor or the bling price.

Hegel stuff is expensive and raved about in reviews, and I'm sure they thought about the way the stuff looks...its design is every bit as intentional as a Rowland or Pass amp.