I guess, in my opinion, it's all a matter of casual playing vs. non-casual playing.
Sorry for the late response, but yeah I see what you mean. It'd be a different feel that's for sure. I do however feel like since things such as SSB being on 3DS could lead to potential Stadium like games on 3DS.
Off-topic, but I picked up Stadium 2 at a video game stand on campus, only issue I had was that it was 60 bucks hahaha. It has been worth it though.