This is like the 4th MLP thing about how Zebras will take over and breed with the whit- I mean the pony folk. I think there might be some serious socio-economic problems being projected onto a children's show, here.
Fun fact: Zebras are more related to donkeys than horses.
All good stories have hint at socio-economic problems. MLP shunned socio-economic problems before and now people pretend the condescendingly sweet and boring 1980s version never happened.