I'm convinced you are the dumbest person in the forums. Please tell me English isn't your first language.
As always:
I'm better than you at this game.
I'm better than you at the English language.
I'm better than you at picking up chicks.
I'm just better than you at everything.
Lol. This keeps getting better and better!
... I'm guessing you're also better at modesty, yes? Oh, wait. Do you know that word? Here, an explanation.
I won't deny that she's a support role, but even the best shot won't land headshots or even score hits every time he/she shoots. It's far easier to SS two dragoons (OHK) than score headshots under cloak on two different targets. Plus don't discount the inevitable shotgun blasts/melees that can follow a shadow strike.
I guess my biggest point is that there is far less margin for error with a shadow than a BW.infiltrator build and that's where she can make up the difference. I would like to clarify, tho, that I don't believe shadows consistently outscore snipers, just that they can.
Note (speaking from console perspective): it's my experience that BW gets 2 shots under cloak and doesn't body dragoons, at least as far as the BW XIII is concerned
. However, I also don't use the BW on the GI or DAI; I could see them bodying a dragoon but I haven't seen that yet (and if we're even bringing GI into the discussion then we might as well not have had it lol)
Yeah, I understand that. SS centric builds are certainly easier to play and... Well, never miss XD They do have less margin of error for sure. My point was simply that an expert player, who knows how to deal with that chance of error and minimize it, will usually kill faster and more efficiently with a sniper, that's all. There is also a weaker difference between a sniper build and a SS one on console, I'm sure, due to aiming being harder. My experience is limited to PC, keep that in mind 
Also no, a shadow can't OHK a dragoon with a bodyshot using a BW, under usual circumstances. I didn't do the math, but I highly doubt even a GI or a DAI could do that, under usual circumstances (i.e: not a ton of debuffs, no thermal packs spam, etc).