The Apples and the Pies might be related.
Big Mac only responds with two words. Marbles only responds with affirmative noises.
Granny Smith, Iggy, and Cloudy Quartz all speak in strange old timey, although outwardly different, dialects.
Limestone Pie is obsessed with the farm and family tradition, just like Applejack.
Maud is an autist from season 4, probably hadn't had the foresight to make her gut the mold at that time. So they just paired her with Applebloom and made them buddies. Implied they had a lot in common anyway.
/mlp/ is filled with autists who can't draw obvious connections. So instead of seeing what they were obvious trying to say you all just go "grey fluttershy" and make bad ships.
Fuck you all.