Nintendo’s upcoming Switch platform will have paid online; a first for any Nintendo system. I personally think it’s a poor value considering past efforts with online support but Reggie did give some reasoning for this move.

“People have taken shots at us for that. The reality is, the way that online experiences have progressed, it’s an expensive proposition. The amount of servers we need to support Smash Brothers or Mario Kart — these big multiplayer games — is not a small investment. There are no friend codes within what we’re doing.” — Reggie Fils-Aime

It makes sense that the servers cost money to run and from the way he is speaking, it implies that maybe the Switch will have private servers and better online quality for the Switch versions of Mario Kart 8 and Smash Brothers. But they need to justify it with more online-enabled games and modern feature support that many expect from online services.
Maybe Nintendo will detail and explain things (like the NES/SNES rental service) in the future and they need to do so before the systems launch. People have little expectation for Nintendo and online services, so it would be wise to win people over.
Source: Gamnesia