As an example, Emchompite says that cards that were included within Japanese sets, like the Secret Rare Yveltal EX from Best of XY, but as promos in English, are usually more expensive in Japanese just due to the nature of their release (i.e., having to pull the card from a pack vs a guaranteed promo card in a product)
The Pikachu Illustrator card is popular with collectors because it was designed by Atsuko Nishida, who is credited as the original creator of Pikachu
Using cards from booster boxes and other sources, you can create a powerful deck to challenge your friends and opponents in the Pokemon Trading Card Game
Usually when that happens, it seems to be because particularly high-value cards were chosen, but I guess that didn't happen here
Fallout went for serialized Bobbleheads, and there wont need to be a lot of collectors who need the entire SPECIAL set of seven for these prices to be higher than expected