Doing the moral, right and humane thing is the thing to do whether you are on a urban farm in the middle of a liberal city with the laws hung over your head and liberals protesting at the edges of your property, or on an island in the middle of the Pacific Ocean 3000 miles away from any other human being when nobody is looking.
Most moral people try to instill exactly that in their children.
It is impossible to appeal the humanity of someone who does not already possess at least a little bit.