We had a guy on our team the other day who literally went into the first room he could find, dropped a trophy system and a tripmine and sat there sniping, over and over. End game, we lost, how many caps did he have? 0. Sadly this is par for the course on CoD, the community leaves a lot to be desired.
I also feel that shooting down air support should count as a kill. The amount of times I'm standing around trying to shoot down UAVs and whatnot only to get killed is ridiculous. At least with a party my mates will usually cover me for the 5 seconds it takes to shoot stuff down, and I will always try defend the guy with a launcher on his back but again randoms don't seem to be able to think of these things.
I'm that guy who shoots down everything. If it flies, I shoot it down. People don't realise how much this actually helps, by not only keeping us off the map but also hindering their score accumulation. I see another AA person maybe once every 5 games when playing with randoms.