Look at Materialize this way.
You (Sigma) write software that will make an iPhone work 50% more efficiently, call it an app. You could set up a website to sell your app to iPhone users. All the users need to know is that you have this great app, then find your website, then send you a check since you don't do credit cards or paypal, then download your app to their phone.
Maybe a better way would be get your app in the Apple iShop (or what ever it is called), which is is already loaded up on to every iPhone and updated regularly. User opens phone, sees app and installs, you get paid for your app. Simple.
Think of Materialize as the iShop, with a large library of apps/software, pre-loaded in a module. The module is pre-installed on 3D printers not phones.
Manufacturer buys 3D printer and starts making product, throws half in the trash because of poor quality. Calls printer maker, printer guy says, you need to use PrintRite, which is already pre-loaded in the Materialize module on your printer, just need to call Sigma for key to unlock. PrintRite is already on the printer, properly configured for that machine, and works great.
So Materialize makes various software available pre-installed, ready-to-use on many different 3D printers (hopefully all some day). Sigma does not have to go to various printer makers to install and test their software before printer shipment or go to the manufacturer's factories after delivery to load and test software on the delivered printers.
Flexibility and cost savings. That's my guess at the concept.