Recettear: An Item Shop's Tale/Fridge

Fridge Brilliance

 * Why will only select individuals purchase treasure-type items despite so many people selling them? Well duh, you run a shop in an RPG. You're the endpoint for useless knickknacks that exist only to generate gold for the adventurers that find them, be grateful anyone buys them.

Fridge Logic

 * An in-universe example. Recette and Tielle are discussing the delicious jelly filled donuts at the butcher shop before one of them wonders why a butcher has donuts for sale. They promptly decide it doesn't matter since they're so good.
 * Well you get Jelly from killing the giant jellyfish boss. Maybe he`s a badass boss runner too.
 * Or he gets his supply of jelly from adventurers. Don't forget -- this is an RPG world, which means that people are giving out sidequests.
 * Reccettear shares a world with Chantelise, and there, a single power crystal can be used to cast a fairly potent spell. Tear confirms the experience gems in this game are the same objects. The amount each adventurer adsorbs for a single level, they would be an unstoppable Juggernaut but Chante's standards.

Fridge Horror

 * It was suggested that foodstuffs never spoil in accordance with typical JRPG mechanics, which explains why customers are able to sell them. That explanation still does not cover the foodstuffs that were apparently "used with love" before being sold, though.
 * You may get a case of this if you start wondering why there are no apples at any step in the "apple pie" fusion. Thought it's not that different from Real Life blueberry pies.
 * Recette was alone with no way of supporting herself for three months when her father left. She has, as Tear notes, a very thorough knowledge of what plants in the town square are edible (telling Louie which ones can harm him, even). She constantly talks about her appetite. It's very likely that Recette was close to starving before Tear showed up.
 * She also has, after a conversion of the house to a store that probably came out of Tear's pocket, 1000 pix. That'll buy you ten of the cheapest food item in the game, assuming you're using a merchant's guild membership to buy in bulk from the source (at the prices normal people pay in the store, more like 8). And considering that dear old dad was at least five weeks away from returning home...