It's not unusual for Epic to disable items; some are rotated in the market to make means for new ones, while other people--such as the guided missile--are actually removed to offer the studio after a while to work on balancing them. But shopping carts Fortnite Items are actually temporarily pulled many times now within a relatively small window of their time. Among other things, they are utilized to glitch into aspects of the map that players must not be able to access, which can be extremely problematic within a competitive game. With Fortnite's massive popularity continuing to elevate, it is no surprise Epic is fast to get anything that might upset its competitive balance (and thereby impact its growing success).
Since the launch of Battle Fortnite Skins Royale a year ago as a no cost-to-play mode in Fortnite, Epic has steadily and quite often rolled out new content. Some of these comes inside form of new weapons, as with all the recently added Stink Bomb, while some serve different purposes, as while using shopping carts and Hop Rocks.
During E3, Fortnite: Battle Royale was launched on Switch, joining the prevailing PC, PS4, Xbox One, and iPhone versions. Fortnite Mobile is also within the way to Android, although a release date to the version hasn't yet been announced.