Except they don't really do anything to advance the plot other than "Planet X is dangerous, here, take this cold-weather-gear/antidote/warning-about-taking-weapons-onto-a-prison-planet", IMO, a completely irrelevant step, especially since you could get that info during the holo call on your ship where you get sent to the relevant planet (& told to pick up any gear/antidote/etc when you get there). If they gave you a mission or two I could understand it, but even then, you get all the other quests on the planet (with the exception of the Belsavis bonus quest line).
I could be wrong, as I tend to get stories mixed up from time to time, but I was pretty sure that one of the classes actually has a story mission or two ON the station. I think it was Operative...or maybe it was Smuggler. Anyway, I just remember thinking, "OOooooooh....THAT'S why this station is here!"
I rotate through my characters fairly often and I have 1 of each class/2 of each role....so...I do get a bit confused on specifics from time to time.