That's a great story about the capybara!
I have worked at several hotels here on Orcas Island, and at all of them we would strive to reunite guests with lost items. One of the more common things left behind was a favorite pillow, usually quite stained.
I work at a restaurant now. A guest recently left behind a bag containing prescription medicines. My first instinct was to check if the medication was something that might cause a serious withdrawal condition, and if needed put effort into finding the person (it was just acetaminophen). The person I was working with seemed to think I was doing something horribly wrong by looking in the bag (I told her I wanted her as a witness). What does the frequent traveler community think?