Well, many things in life are preferable but you don't always get them.
[You must be logged in to view images. Log in or Register.]
The druid is a pretty well rounded class. If you consider ports and track they are probably the best rounded in the game (for overall gameplay).
If you have an enchanter a druid vs shaman for healing isn't a big deal. Even if you have a bard slowing/cc'ing a druid can keep up with heals. Ultimately you need a tank, CC (sometimes), and healer...the rest are just dps and can be filled by many classes. I guess even a Druid can be group DPS but it's a pretty crappy spot for them, imho.
On raids, especially in Velious, they become backup healers saving DPS from dying and providing group buffs like thorns and resists.
Many people re-roll from a Druid main for another class. Part of being frustrated with not being the "best" at much for the little min-maxer in all of us.
Note: Realized after writing it that you all mentioned things I did. Too lazy to edit and make it sound brilliant.