I think they're jealous about us being the larger, well known fandom.

First off, I don't care about anything haters say on the Internet about our fandom.

Just the one common thing I hear is "Stop ponifying and making crossovers of everything Bronies you ruin it!" confuses me.

Sure, it can be annoying seeing your favorite show being ponified and crossovers made of it. Ironically, I discovered this show from seeing Futurama crossovers of it. It annoyed me at first, but then I ended up liking MLP FIM, so it didn't annoy me anymore.

So whatever the crossover, may it be bad or good, or some weird crack shipping it in some way helps promote a lesser known fandom. Well if it's a very good crossover, it can help a lot.

Even if you hate or like My Little Pony or anything else of that matter, whatever the crossover is, it helps those of a larger fandom discover your smaller fandoms.

So even if crossover "X" with "X" annoys you, in the end it helps both fandoms.

Though it might be very insignificant help if the crossover is bad.

So in conclusion, if haters of "X" and "X" crossover just say something along the line of what I said here.

Or say nothing, whatever you want to do.