The Equestrian/Human Manual - Rule 018

I'd like to point out that Equestria's cider is "soft" (contains no alcohol). Fermentation is a very long process and can take many weeks. As we have seen in "Super Speedy Cider Squeezy 6000", Equestria's cider production is superfast, leaving no time for fermentation to take place.

This gives me an idea. If you haven't done it already, you need to include a rule that forbids bringing alcohol to Equestria. Horses are generally quite tolerant to alcohol, but here we're talking about small horses that have never been exposed to alcohol, which means that it can have a strong negative effect on them.