It didn't pretend that.
Everyone who can read could see it in the description, both in the iOS appstore and in Google Play.
Well, I don't think people really read the description anyway (not saying that's Nintendo's fault). I wouldn't know much as I've never downloaded or played the game, but I vaguely recall the game's Play Store page saying "Free, with in-game purchases" or something. That's what people are gonna be looking at before downloading usually, and while it's not false, it is misleading.
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