Forgive me for I have sinned:
I no longer carry wands. If I have a wand, I've bought it for regular group that I travel with, just in case. But I don't carry wands anymore. It does add up. You've touched on a couple of issues that I see and I'll break it down:
The Healbot vs. Battle Cleric debate: Never understood this as a cleric--I'm neither. I'm a cleric. I will almost never "hang back" and just heal. If there's a mob, I'm squaring off with an archer or a caster, until someone else can engage. I'm all for scrimmaging. At the heart of this debate is some basic common sense. It's situational. There are quests, that despite your parties make up, any cleric will need to "hang back" and heal. To do otherwise will be a party wipe. There are other quests were my best use is to "put a blade on a critter."
Communication within the party is key. Don't assume clerics are carrying wands, most of us don't. Our blue mana bar is usually it. We have expensive shopping habits at the AH too. Inform us of big battles to come, buffs needed, etc... (I'd also like to confess that I do "carry" FoM. There was an unfortunate death on the plateau of Giant Hold--a certain frustrated female mage wailed during an Ice Storm--while she was meleeing--"I can't believe our cleric doesn't have FoM!!" I did. Didn't think it was going to be needed--cast it on everyone--but her--which is why she died =)) Here's a tip kiddies: Never speak about your party cleric as if they aren't there or they are a hireling. We have tantrums too!
Cockiness is supreme arrogance and this is the worst. These are the "eliters" who must do every quest on elite, even though they are sorely pressed to complete the quest reasonably well on "hard." I've begun to avoid these groups. It's basic math here to an extent. I have so many SPs, there are so many shrines, and the party simply isn't built well enough or equipped well enough to beat the adventure without it being a slaughter-fest.
There's no better feeling for a cleric to make it to the first shrine in a quest with half of their mana bar still standing! It's a sign that you have a good and well equipped group. Likewise, if your cleric is out of mana constantly from heals, the party needs to concede that it's in over it's head.
Self-sufficiency is important. We clerics die too and unfortunately we can't use our wands while we're dead.
Still I will never subscribe to following a group about and constantly casting heals. Should a party want this, I would suggest a hireling cleric.
I am surprised at the number of people (rangers, bards, and pallys) who give a "ty" when healed. Yes your mana bar is full, but I look at it this way--someone's gotta get me to the shrine if I go down--so why not? There is no right or wrong here, just the need for communication (and FoM for a meleeing mage), and acknowledgment of what a party can realistically achieve.