Answer: Bassanio refuses gold because he knows that "all that glisters is not gold." He also refuses silver, calling it "common drudge 'tween man and man," as coins are. He chooses lead because he knows that true worth lies inside, even if the outside doesn't look like much.
<em> -- Cited from Scottexteriors.com </em>
I would say that two uses of animals that could cause conflict in our society would be the fact that people use them to race and or "Fight", in particular Dogs. Also, people use animals for testing specific cures for diseases, in particular, a rat. "Lab Rat" is what people use for that.