Weapons have a purpose in PvP.
Storylines run out quick if that's even half of what you spend your time on. Escondida will be explored in a day and will be old in a week. Ship upgrades as an end game source of enjoyment is almost contradictory to what you've been saying - ship upgrades are just like rare weapons. They help you get stronger, but once you've got them all, then what? No more goals to achieve. Then you're stuck with the same problem you'd sooner reach if trading was implemented. Nothing to improve, nothing to do.
Looting is a major aspect of this game, no matter who you are or what your stance on trading is. So the concern about whether or not it's implemented, or even the opposition of it, is perfectly reasonable. I personally wouldn't necessarily hate for it to be implemented. It might be annoying to see twice as many people walking around with weapons that are supposed to be rare and hold real value, but heck, that's all pretty much gone out the window already considering how insane fishing loot has been since the start of beta. I'd get over it, but it's perfectly understandable to me if some people would be too frustrated to let it slide. And I don't think them holding such an opinion is something to poke fun at, either.