> They seem to be deliberately choosing art that's behind glass. That gets them maximum visibility without causing priceless damage. In the video they say "don

> They seem to be deliberately choosing art that's behind glass. That gets them maximum visibility without causing priceless damage. In the video they say "don't worry, it's behind glass", or something along those lines, so the decision indeed seemed deliberate. Besides, kind of hard not to notice whether you're glueing in your to glass or a painting.