Probably because the 5 vendors each sell unique weapons and armor to use in PvE. I think you know not all gun types are created equally. I prefer to use as many as possible before investing resources into one that stinks compared to another. It now seems like every 3 months the items we work hard on to upgrade become useless compared to vendor gear makes it even more sense to pick and choose wisely. It's hard to find the load out to enjoy if you don't have time to pick and choose what you like. Same with armor, why use armor from a single vendor which boosts weapon types I don't use? That was the only reason I leveled the factions and crucible vendors for. To get a feel of the best weapons to fit my play style while avoiding PvP. To the haters, I don't want PvP removed or nerfed, just don't want to be forced to play it to access 80% of the vendors in the tower. 100 marks a week doesn't give one a lot of options. Having a Cryptarch screwing you over for almost every engram he decodes doesn't help. If the RNG gods start to shower us with weapons like Borderlands this wouldn't even matter. Green and blue items stink. Not sure why that even drops for anyone level 20 or above. Unless I am in the minority, I have thousands of weapon parts along with thousands of salvaged armor parts for each class. Do I really need tens of thousands? Maybe DLC will provide a use for them.