I'm not saying this is wrong or right, but perhaps some people feel everyone has a duty to do something meaningful to push society forward, otherwise they are essentially free-riding on everyone else's sacrifices.

And that something may very well be as broad a goal as "do your very best, everyday".

Sure, you can't force people to see the world through that same lens, but you can certainly pick partners based on traits which you admire, ambition / grit presumably being one of such traits.