I've always seen the hard moves from UaPJ aimed to strike every character in the group as a default (just like hits benefit the whole group). Sure you can go against just one character because the fiction dictates so, but you also can deal damage to the quartermaster for the same reason; or maybe the scout finds something different from a monster and it's no more about HPs; indeed, you don't even need to target the character that rolled a miss, if it makes sense. Maybe if they already knew what dangers await for each role then the decision makes sense, but otherwise, it's just about wild guesses at most. And I tend to improvise a lot on the spot so this could rarely happen :P
Also I feel it "right" that different kinds of risks are linked to different stats.