I don't see why not, I mean if you can connect wirelessly to the router and therefore to other people around the world then it stands to reason you can instead connect to the console next to you instead. Even if you cant then the "All connect to the router then join the same game" approach would work also with great ms/latency as you're right next to each other.
Internet should be free also, all you're doing is using a free web-browser Opera, which I'm using atm, and connecting through the internet which you already pay for really Nintendo are giving you nothing extra for this, you don't get charged of microsoft or Apple etc when you surf the net with their computer.
Internet should be free also, all you're doing is using a free web-browser Opera, which I'm using atm, and connecting through the internet which you already pay for really Nintendo are giving you nothing extra for this, you don't get charged of microsoft or Apple etc when you surf the net with their computer.