There are many, many game publisher tactics that I would call scummy. Nintendo's actions included.
If "selling a pass in advance" is even on that list, it's very near the bottom.
I agree it isn't nearly as bad as the most common stuff seen in the game industry or other shady practises seen from Nintendo, but charging 30 bucks for something we know nothing about is pretty bad. All we have is that there's an exclusive costume, 6 characters and stages. What we don't know is who the 6 are, what stages those will be, what spirits and how many will be included per challenger pack, how many songs will be included, yadda yadda yadda, we're going into this blind and being told to fork over half as much cash as a new AAA release
Like what? Pokemon is obviously a problem, but TPC is the problem there. The only real problem is their mobile games. But that hasn't spread to their console games. Name one nintendo (console) game with microtransactions. Name one nintendo game that was rushed into production to meet a deadline. Name one nintendo game where the staff was forced into crunch time.
The F2P Kirby game has microtransactions and is on 2 Nintendo systems, there's Rusty's Real Deals, the Pokemom Trozei game on 3ds, etc.
Crunch is something Nintendo doesn't seem to do nearly as much but that doesn't mean they're saints, look at Sakurai overworking himself, Nintendo doesn't step in to stop tgat and as Sakurai is a freelancer despite having worked exclusively at Nintendo for the last decade, he also gets less benefits. Nintendo also hates union actors, adores artificial scarcity and has many, many other consumer unfriendly practises as a whole