C: you like many others are not "born" snipers
D: its not cool like the video games.
Sums it up pretty nicely. Also, most games people play focus on close combat, and thus are very short.
In longer scenarios, sniping can be viable, but it takes a LOT of patience and care. By patience, I don't mean waiting around for a few minutes for a target to appear. I mean taking 30 minutes to an hour to crawl into position, then another hour or three to wait for a
lone target to enter your line of fire. Not taking extreme care with your movement and shots will undoubtedly end with you getting hit before you can do anything.