The things that they show (running a web site with lots of UX, slicing, image processing, materials data, catalog of customizable designs, etc.) fit pretty well into a powerful web site/service with a small CPU in the laser cutter. Adding a powerful CPU, etc, would add to cost and complexity - it is much easier to run a web site than to support thousands,of users' local installs, etc. Though i agree that makes the device dependent on their service, that's becoming a pretty common tradeoff these days.