It's all about the snob appeal baby! OK, not so much.
Seriously.... Scotty uses German Stainless Steel (GSS) which is a quite expensive material. The way each putter is milled also plays into the overall costs of the product. Then there's the better than average cover, so you roll up to a big cost.
Here is my take. I started using a Studio Design 5.0 about 6 years ago. I just love this putter and have never felt another that does the trick for me. As we all know, once you find something that works (mentally too), you just stick with it.
Finally, there is the Custom Shop. No one else lets you send in you putter for personalization and customization like Scotty does. Think of it as the ultimate MyJoys experience. My putter is 100% "mine". My color scheme, grip and initials. No one else has one. Shaun is the same way, as he bought one of my Cameron's last year. Ask Nock Poz too, he's a big Cameron Collector guy. It's just the best out there....