I bet, especially back in 2011 (only 29% of US population with smart phone), people often went and used their computers for free for short personal tasks too, say checking email.

Is that obviously abusive (and specifically criminal?) too? Maybe not?

So it depends on what you are installing software for. I thin it's not just a question of "simply walking into the store and quite literally installing a small application" being obviously illegal and/or abusive. That's all I'm saying, it's not so clearcut that simply becuase he installed software means it's "abusive" (let alone criminal).