Making snipers exit the scope upon taking a hit would be so broken. Don't try to argue that [i]halo does it so it will work[/i], that's bullshit. In halo the sniper is just as accurate when hip firing as when you are so in your scope so therefore there is technically no need to use the scope at all, while destiny on the other hand is at least slightly more realistic making hip fire horribly inaccurate. In destiny getting shot while trying to snipe someone would make you miss no matter what you tried, unless you were at point blank range (you probably wouldn't use your scope anyway) then you would be guaranteed to die. This in turn would increase the amount of people looking to camp as far away as possible making them even harder to kill.