I don't think even casual people would like this "game" there's not much to do in it and wii sports was a free tech demo. and I don't care who you are if you spend 50$ on a new game you deserve a good Experience. there so many great party indie games like jack box that are cheaper and a lot better. not everyone is made of money and if I was young and asked for this game I and my parents got it for me I would have pretended to like it. because I would have felt so bad making them spend money on something I didn't like. and I don't even come from a super poor family. new video game are just expensive 1-2 switch is 65$ CND
Many casual people genuinly liked wii sports, it was their favourite game
Not all people like games such as mario zelda FF the last of us call of duty etc etc.
Also wii sports lose sold pretty well, it even aquired a nintendo selects release in the west, furthermore in Japan wii sports was not included with the wii console and it was one of the best selling games.
I'm pretty sure that it is mainly thanks to the casual people that wii sports was such a succes since I highly doubt that veterans would like that game. Also many kids especially girls actually like these kind of games. I'm not kidding I have seen it with family members, family members of friends etc. It's no suprise that wii sports was one of the best selling wii title since those games have an impact on casual people, all my family members are not into gaming, they don't really like games such as mario or zelda, yet titles as wii sports and just dance peeks their interest while other games are pretty bad in their opinion. Not for all casual people but it does attract quite a few people.
If nintendo advertised this crappy game well, I'm pretty sure it will attract many casual people, especially girls. might be a bit sexist but that's just my personal experience with such games.
Everyone has other intersts. If one finds something interesting for others it might be total garbage. You cannot judge what certain people like or not.