Promoting the feature that it dissolves in acetone (and one day water) seems like this is being designed with nefarious purposes in mind. A robot that erases all traces of itself after completing its mission.
1. If you had read/comprehended the article you would understand how they plan to address this concern.
2. Really, even without reading the article, your comment just shows a failure of imagination. It's really not hard to see how this early prototype might be developed into more mature, useful applications.
Demoing that you can (partially) dissolve something in acetone or even water is not terribly impressive, even if their self-folding and mode of locomotion is pretty cool.
Except these are driven by external electro magnets.
But I agree that people seeking rent will be a problem. As usual.