@Xai:
This can actually make sense irrespective of whether Rayleigh selectively aimed his Haki burst or not.
I'm not sure where your scenarios differ. Are you suggesting that in the first scenario, he included everyone (IE: Camie, Pappag, Usopp, Nami, Chopper, and random slaves) in the burst, but he "had to"? And they are "serious business" for withstanding it?
Why the likes of Bon Clay or Usopp don't faint is simply because their willpower is strong enough.
It isn't just that Usopp didn't faint, or that Bon-chan didn't, or that Camie didn't, or that Pappag didn't, etc, etc, but that they didn't even feel dizzy afterward. No reaction outside cluelessness. They apparently didn't feel a thing. And that's not all, Rayleigh specifically apologizes only to Law and Kidd's crew– who visibly and verbally felt something-- so it doesn't really add up that he would do something that could easily affect his allies (Hacchi and the SHP's), but only apologizes to Law and Kidd's groups. Not to mention he is clarifying that he didn't realize they were friendlies of sorts, which could imply things would have been different had he known. I mean, what was the purpose of having Oda stick that sentence in there in the first place?
I always figured it like this, you can aim it at one person, or do the "blast" which can't aim but will not affect civilians, only warriors.
How do you define civilians? For that matter, how does Ambition identify civilians…?? No offense, but that seems a bit left fieldish...