Blame WoR, and Seananners....and every other 1337 gamer who rose to fame because they never moved, and just killed what was placed in front of them.
They are the equivalent of the proud zoo hunter.
Yeah, you killed he sh!t out of that tiger in the cage, but that doesn't mean you're a good hunter.
The rise of the d-bag came when killstreaks stacked, and people were rewarded for hiding for 25 kills, with 85% of the kills coming from AI streaks.
Their game was hinged soloely on the good nature of the community who still played with integrity--they just fed these opportunistic h0m0s kill after kill, reducing the rusher-to-be into a cautious player, and further solidifying the elite beliefs the camper had of his playstyle.
Eventually, the cycle produced corner camping, window hanging, bush hiding, ground-shadow laying, kill-and-move, kill-and-move players who's sole aim was to put up big KD numbers with a total disregard for objectives and victories.
Can't count the numbers of Machinima videos I saw there the guy lost, even though he went an "incredible" 85-2 in domination--WITH NO CAPTURES.
Kids in my era who liked basketball, grew up as sportsmen and ambassadors of the game, because they watched and learned from Michael Jordan. Now they watch this current crop of @ssholes and become like them. What they see is what they learn. What seems to bring success, they aspire to and copy.
It doesn't hurt, however, that camping is so fcking easy to do. ADS'ing is without risk and without unpredictability. It's safe and it normally produces great results--otherwise it woudl be a dying strategy.