Don't hate me, but: Smash and Mario Kart are the two franchises I really don't care for, but I always end up getting each entry for each Nintendo generation because everyone else I know loves them, so I need to have them on hand for local multiplayer. So, I guess Nintendo shouldn't care because they'll get a sale out of me anyway :|
That's how I feel about Smash Bros. I play it socially with friends but I never go to play it solo. If i want to play a fighting game I'll go play Mortal Kombat. Mario Kart, on the other hand, I actually enjoy a lot (but most of my friends seem to only get it to play it with me because I like it so much).