Geez guys, you've taken this discussion to the center of off-topic city now .

[Sniper]
These guys main strategy is to get an explosive weapons and
camp in a hard to hit spot raining grenades or missiles down on your
head. These guys are annoying. I find the best strategy against them is
to ignore them, or wait them out. They have to come out for more
ammo sooner or later, and when they do, load them full of buckshot.
Snipers tend to have very poor engagement skills, which is the main
reason that they snipe in the first place.

And

[Camper]
These guys are pretty easy, usually. They just sit near
respawn spots with a weapon, and try to kill whoever
respawns there. Usually you can sneak up on these guys, because they
don't pay attention surroundings. Not only that, but they will rarely
get many frags, because they don't hunt people, get armor or ammo...They just sit there.

Of course, definitions get out-dated, games evolve, and one main inconsistence is the lack of items in E+ that are worth defending (aside from the occasional power-up, of course), but, in general, i don't think much has changed since then. And imo, Giz is neither, he's just a Sneaky Bastard