All I can say is where I'm coming from. I'm not suggesting or branding anyone any names such as thief or whatever. I see gearing up companions as an inherently optional practice (maybe greedy might have some "bad" connotation to some people, but I'm meaning it as an option that you happen to have a taste for). It's not needed, even for leveling.
I got my Bounty Hunter to 50 just fine without much of a fuss with any of my companions "needing" to be upgraded.
I'm having no issues with my sorcerer at the moment either (it's still pre-20s though).
I'm alright with the "play it by ear" situation-based greeding/needing of it. I just find adding another roll button overkill. This is almost a non-issue if you look at it with a impassive view of...it's loot. It's going to drop again. You loot to play the game (getting better gear helps you get further in content, as far as end-game goes), you don't play the game to loot.
Gear as you're leveling there's so many ways to get gear (from quests, commendations, world drops, flashpoints, vendors, GTN) that leveling is more important then getting better gear. As soon as you get the gear you want at lvl 20, it'll be obsolete by the time you're 25.
I've actually had someone needing a tanking weapon for their companion before, at first I was wondering why they did it with annoyance (because I didn't even think about it as something to do), once I found out I laughed it off. Also, after my initial reaction, I looked and noticed I had a modifiable weapon anyway. All I need to do was get a new barrel with my commendations. (I actually have a blog entry about it: http://finiteuniverse.com/2011/12/the-old-republican-entry/)