Seriously, there are worse cases out there with “legit” businesses.
And why should these cases be an argument against 3D-printing?
All you need is some kind of regulation – if you sell something you have responsibility for it, if you share it as with FLOSS (take a look at the GPL license – it’s your issue if your computer blows up) then the user has to be aware of the risks.

And it has to be easier to have things tested – there are CE marks in the EU for a reason, and if anybody could get their creations tested according standards, then this would not happen.
Why not test for toxic materials and if it’s stable and can hold a certain wheight?
And the case where the site got hacked – as if that couldn’t happen to anybody else as well … Oh, wait a minute – IT HAS!