The lack of available stl files is not even a pebble in the path of anyone out to rip off their tech. If they lack the resources to buy one, tear it down, and come up with their rip-off design without Solidoodle's stl files, they're never going to do anything.
The end user, however, can be further monetized by making the parts only available for sale. Especially if you only sell the complete carriage.
I support their freedom to do business this way. I just think their secretive nature about everything is silly and hurts their goodwill from the community.
I think another reason for their secrecy is that if there is any "intellectual property" in the machine it's likely in the form of patents owned by the big players.
For now, you just have to hope that a Lawsy or Ian Johnson, etc. has already broken the same part as you or else you're up to bat. Thank god for those guys! I agree with what several others have said that the community will design improvements when problems are encountered. I am certainly a grateful leach.