I really don't think having some poor people working in slaughterhouses, treated slightly better than the animals they butcher (but only slightly) really improves anyone's sense of empathy for animals (or humans). That ship sailed a long time ago, around when we got factory farming or really once any family didn't contain at least one farmer (1800s?)
To anecdotally confirm what you said: There was a "scandal" in Germany last year where a school slaughtered and barbecued a hare. (Students were around 10/11 years old) Parents were outraged, basically arguing 'it should be everyone's choice to either know or ignore where meat comes from'.
