To be honest, I don't really know. If you're referring to the
pricing on the Berry Market/GTS, then I'll say that because the
price of a berry is completely dependent on the player selling them
(though the majority of them don't tend to go above 1-4 PD), some
players mistakenly price their berries way higher than what they're
actually worth. If you're referring to a berry in the Item Shop, I
theorize that it could be because of the berry's rarity and the
meals you're able to create with it. I don't know, but no berry is
worth that much PD. This is simply because, though there are a vast
variety of them, berries don't actually serve much of a purpose on
PokeHeroes outside of being fed to Pokemon and cultivated in the
Berrygarden. I don't recommend purchasing any berry priced
significantly higher than others unless there's a clear use for it
and you can't get it for a better price elsewhere. ^^