organizational behavior 101
Failing to take care of your volunteers -- to thank them, to give them the resources they need, and to keep tabs on them to avert burn-out -- is fundamental. When you start taking people for granted, you send the "you owe us" message -- or worse yet, the "you don't really matter as a person" message. And that's when people start asking themselves if they really need this grief. Maybe it's time to drop back and let someone else organize the events, or do the scut-work, or reach out to new members, or whatever. And then you get into this downward spiral and it's very hard to recover.
I'm fortunate that my congregation doesn't have these issues. Some of that's luck, some of it's clues, and some of it's the fact that we're large (so it's hard to really drop below critical mass). But I've seen occasional presumptuousness on the part of some leaders, and I try to bring it up with them when it happens. Because I don't want us to end up with those kinds of problems. I've also seen it in other organizations, and sometimes I feel helpless to change it.
I thought some of my friends might be interested in discussing this (either here or in Daniel's journal), so rather than just commenting there I'm making an entry here. Besides, Daniel is new to LJ and not all that connected yet. So go say hi or something if you like; he won't mind.

It depends
Let me give some examples of the above:
If someone really doesn't realize what they're doing is going to cause offense or mess up someone else, then sometimes all they need is to be politely informed. But sometimes the cluelessness goes deeper right into having problems understanding the difference between right and wrong. There are people (too many) who really think, for instance, preferential treatment of their pals is an appropriate use of the offices they hold. If you are dealing with someone who really thinks that, say, being the worship coordinator means that they only have to listen to their buddies ideas and only have to please their buddies' tastes, the problem really is getting them to understand that that's, at least, not socially acceptible, and, ideally, a Wrong Thing To Do.
Something else which adds a different spin to the ball is that some people don't care about the long-term in a given situation. Someone might hold a committee post because "someone had to" and they were strong-armed into it, and they have no identification with the job and see it with disdain as an irritating chore. Trying to tell such a person that they way they're doing something is going to have long-term negative consequences might not only cause them to laugh in your face, but actually give them the idea (possibly pre-consciously) of doing the job poorly to sabotage the group as an expression of their irritiation. If you think such a person is well meaning, sit them down and level with them. But if you think such a person will only feel more badgered by the burden, the only solution is to get them out of the job.
Sometimes people do things which seem clueless and/or petty because of differing cultural expectations. There are people who see all argument as hostility, and there are those people who think argument is a form of recreation. Putting people of both sorts on a board of directors can cause spectacular fire-works. From both sides, the other side is clueless and petty (those who are anti-argument seeming to be repressive and marginalizing, those who are pro-argument seeming to be antagonistic and unable to play nicely with others.)
tangent
Or entertainment. :-) A few months back I and another board member, who are both of the latter persuasion and each knew this about the other, went all-out at a board meeting over a proposed bylaws change, while other people looked on somewhat aghast. We had to explain to them that neither of us was mad at the other (and in fact we like each other), and that this really was the best way to hammer out the bugs in the wording.