Another valuable point to consider while extracting goods is what other players have (or don't have) on their backs. If there's a player hovering around the helipad without a yellow canister on his back, there's a fair chance he may want to kill you and steal your stuff, all the more so if he's with a group of others who also don't have any loot. On the flip side, if you want to gank someone, it's probably a good idea to at least pick up one item beforehand so it looks like you've got some loot and therefore aren't giving yourself away before inevitably opening fire.