‘The Pokemon Weekly’ cards weren’t only available in those boxes. Those boxes were specialty products. The cards were primarily released as vending cards.
As for the pricing discussion, people started realising how scarce they are (those boxes & the cards they contain).
As for the cards, take a look at this listing. The cards from that auction are not grade-worthy, nor did it contain a full box. Yet people still see the value in them. I would be extremely surprised if they retrace to the level they were at, when they are still relatively cheap. I don’t think the people buying them will lose any sleep over their purchases.