I still laugh about their first foray (as far as I recall?) - New Super Mario Bros 2 on 3DS. It was like, what... $5 for 2 Mario levels? And that was the worst of the modern Mario games to begin with.
I think there were DLC levels in Pikmin 3 as well. Shitload of DLC in Smash, and don't even get me started on Hyrule Warriors (although in fairness that was really not a first party title).