Well I originally had an SGA on every character the same with bad juju they got dismantled just before HoW. The extra two sga's, cause I still own one, I got because you needed exotic shards at the time and killing a few people with a machine gun was cheaper than strange coins. The extra lord of wolves I got because, well weapon parts... I was going to do arena anyway so why not earn another shard and some parts whilst doing it. The objective for me of destiny is to maximise my rewards for in game time, you may see it as pointless but I'd call it future proofing.