The difference is not between two cars, yours and mine, but between a passegner ship and a cargo ship, built for two different purpose and two different class of users.

That seems different to what you were saying before.

This is well explored in "Three worlds collide". Yudkowski vision of morality is such that it assigns different morality to different aliens, and the same morality to the same species (I'm using your convention). When different worlds collide, it is moral for us to stop babyeaters from eating babies, and it is moral for the superhappy to happify us. I think Eliezer is correct in showing that the only solution is avoiding contact at all.

There's not much objectivity in that.

Why is it so important that our morality is the one that motivates us? People keep repeating it as though its a great revelation, but its equally true that babyeater morality motivates babyeaters, so the situation comes out looking symmetrical and therefore relativistc.