I've noticed that some items that used to be really common, such as the Black Candy Bar, The Slots, and the Slots Trading Card have suddenly become very high priced and there are none in the shops. Can someone tell me what's going on?

There are none in shops because they are glitched in the Shop Search. They ARE in the shops but don't show up.

Black Candy Bars are expensive because there's an Achievement where you need 25 of them.

The Slots items are more expensive now (but really not too much) because the Recycle Beats asked for the book and sporks already and people hoarding the other items for future Recycle Beast requests.

There's an achievement for feeding black candy bars to a pet. The recycle beast often asks for slot items, there is now a Rb achievement as well.

The candy bars I've heard are glitched but mega crazy inflation isn't un-common on here, just a part of Subeta everyone gets used too.

Ah, thanks, that had me confused.