Several things return from Super Mario 3D World, including Piranha Creepers. However, in Captain Toad, they behave a little differently, as they're knocked back much futher when fallen upon than they were in 3D World — in fact, they're knocked back the same amount as a Ground Pound would deliver in that game. While this initially seems like a gameplay tweak to make them manageable in a game where you can't jump, the reason for the inability to jump actually explains it. Captain Toad can't jump because his backpack is so heavy... but because of that extra weight, he hits as hard as a Ground Pound when he falls!
