People fear what they don't understand and these people don't understand why bronies like MLP we're the Zecora to their "Zecora is making Apple Bloom soup!" forgive them for not understanding and if you are particularly kind you could even try to show them that there is nothing to be afraid of if they are willing to listen. They are just scared people fighting back the only way they know how, through harsh words, they are afraid of having something new in the (usually online) places they go and they can't do anything about it, but they don't realize what you all said, bronies don't change the internet they add to it. And if all that doesn't work we could always give them The Stare.
iv;dp version
They are scared and can't do anything but kick and scream, be nice to them they will come around or fade away eventually.