Yes, that's true but those seem to be more just part of the stage, not items. Since the creen is moving upwards like the iceclimber's level on SSBM I think those are just there to help you get up. Whereas the eggplant is just sitting on a platform that seems to be there the whole level making it an (almost certainly) an item.
I haven't really seen much else except there are paper shy guys on yoshi's island
Also I was kind of wondering about the rubber duck on the ultimate chimera's head in new pork city... I guess that is just part of it...
Anyway. I could see stages too. Like an exclusive halloween stage made from nintendo not just a fan. Like for chirstmas north pole or something. Halloween a haunted castle. Easter kinda like poke floats where you hope around eggs. Valentines day. They could be creative with that. And the list only goes on. This would really be nice if this happened.
@sam I doubt that would happen. It would be unfair to those who weren't aware of that offer and didn't unlock the character. It would only work if there was another slightly harder way to unlock him/her.
Possibly a day and night feature, maybe I'd like to see that, but I'd always been playing at night... Wifi, eh, I suppose it could always be day unless selected otherwise. Maybe even introduce weather that'd annoyingly push you off the stage? Like the tree in the Kirby stage...