MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
"Of course they don't have to give away their designs for free. But that is what Thingiverse is about, so then don't post it here."
Incorrect. Show me in the TOS or About page that designs must be free. If you read the TOS, there's already accomodations for user-to-user payments and other commerce.
Your complaint was "object here should be fully downloadable." Well, they are; every object on here is fully downloadable and even CC licensed. This site is partially about discovery and this is perfectly consistent with the purpose of allowing your creation to be discovered. It's not against any of the TOS to use the site to host test files for models that require purchase.
I, for one, am happy that they posted them here because then I get to KNOW about them... otherwise I wouldn't. I was happy to pay for the model but especially after seeing the quality of the parts before purchase too. Wonderful thing about Thingiverse. I hope they don't change that.