I see this as a "you're technically right, there is a legal difference; BUT the issue here is not how it was passed to someone else and not returned to the owners, but that it happened at all" type deal.

Yeah, sorry I left the name out cause I saw someone had already said, but Japanese Beetle. I've also heard them called potato beetles but I'm not sure if that's correct.

KILL IT!!! As sad as that makes me to say.. These guys are brutal, if they reproduce in large numbers (and they do that fast) they can demolish entire plants in days. Now, I'm in Canada where these guys are an invasive species with no natural predator, so of course look up what to do in your area, they might not get so out of control in Colorado. They're so hard to get rid of when their population explodes so I'm always out in my garden on the hunt for them. Hopefully that's not a problem where you are and he can keep on snacking safely, but at the very least keep an eye out for them!