I don't understand why people dislike colour coding rarity. It is soo convenient timesaver, from player's point of view.

The most important point, rarity is NOT about the value of an item. It is about the uniqueness of an item. The colour code is yelling "check me, I'm an interesting item, you might like me!" The grey items are what they appear, no brainer choice, you never check the stats because you know what these are. Blue items might have what you need but only if the item type is to your needs. Gold items are always to be check regardless of type because these can have very rare properities.

Personally, I feel that any game that use rarity as a perfect indication of item value is broken.