@dziadek1990  
Nah, they just give Applejack a lot of mary jane to deal with all of the crazy ponies. She also makes her own ‘special’ cider in the barrels in the cellar.

@SunnySide  

 
I wonder how psychotherapist offices work then.
 
“Oh, Ms. Applejack, I am so sorry, but you seem to be sane. :c
 
This is way, way outside the norm… but please don’t worry! Here: have some antipsychotics psychotics. :) “

@dziadek1990  
They’re ponies, and literally every single one of them is a crazy.

@SunnySide
 
I just realized the potential for a truly malicious marketing tactic against Earth Ponies: put addictive substances on the surface of the doorknobs to your businesses, or on tools you sell or other non-edible mouth-held things.
 
Soon enough, Earth Ponies who didn’t open your business’s doors or didn’t use your tools for a sufficiently long time, will have withdrawal symptoms.
 
“I don’t know why, but visiting Home Depot too rarely gives me a headache…”
 
Now the question will be: how long till the malicious practice is discovered?
 
Twilight both in the S1 premiere, and S2 finale shows paranoia/conspiracy-theorist sympthoms. How many other ponies like her are out there?

@dziadek1990  
There was once an idea I sort of came across that mentions earth ponies might just use bidets. I’d imagine there would be a similar one that’s adjusted for use in earth pony changing tables. Just towel dry a bit and all done. It’d be both unhygienic and silly to just use your mouth for everything :P

Realized an implication with a delay, so I will clarify: Pinkie is using wet wipes (held in mouth) to clean the twins. She is not cleaning them with her tongue, like a wild animal.