I think the best way to shut up bitcoin haters is to prove that you are earning on bitcoin. When I was starting at bitcoin, there are a lot of negative comments from my friends and they were always telling me to be cautious. Only a few of them supported me and those people are investing on bitcoin as well. They are earning enough money for their needs and they never regret investing on bitcoin even if the price goes up and down.
Proving to them about your earnings is not yet that best way to shut up bitcoin haters because like here in our place even though they saw that we earned profit from bitcoin still they hated bitcoin. You know we can't avoid this kind of hate but as an individual who knows bitcoin more we should continue what we are doing as long as we can't commit crimes.