I have a great relationship with my Principal and would not think twice about going to her about something like this. I have the luxury of having only one front desk person in my school prone to having a difficult day EVERY DAY OF HER LIFE and can count on the other one to pull us both through. I would aslo suggest the --do not do their work --idea would get your point acoss sharply.(Pun intended) Just think of all those days you can enjoy in the summer out of the office and on the beach! And I will also say, even though I over look alot, the KILL THEM WITH KINDNESS routine is getting real hard anymore and may be highly over-rated. (Could the end of the year be close?)
I would have to say that talking to the principal might not be a bad idea. Of course we should always be nice as can be to everyone. Sometimes the principal is busy with alot of other things and might just assume that everything in the office is going okay. If the principal is not made aware of the situation, nothing can be done about it. I know that I've talked to our principal about things I didn't like in our school. I always take the approach that I don't want to make a big deal about it, but myself and some of the other parents feel a certain way. Our principal is always very careful not to make it known who talked to her. In fact, she's waited a few weeks after talking to me to make a comment in case someone knew that I talked to her. Hopefully your principal can be very proffessional about it. Just my thought on it.
Gee Ohiomom that was the advice given to me two years ago. I will say it worked (esp. in rasing my BP). Be helpful but maaybe NOT TO helpful. Help the kids, do your stuff, but DO NOt do the work they are paid to do and maybe they will come around to you and be a little nicer. I am not saying advertise that you aren't helping them but be a little "too busy" yourself.
This may not seem like the advice that you are looking for, but I think the best thing that you could do would be cause no additional waves and then just "Kill "em with kindness." Believe me, I know that it is hard to bite your tongue. I've felt a couple of times like I needed stitches. However, the next time trouble arises, bring it to the principals attention or to your superintendant if that doesn't work. The next time something like your cheesecake disappears, instead of going to the office staff, do one of those conversations with the principal where you say, "oh, by the way, a fundraiser company dropped off a cheesecake and I can't locate it, could you help me." They will know of the incident and I'm sure that it probably won't happen too many more times. The kill 'em with kindness comes in when you just are nice and pleasant and so sweet that they just can't stand it. Keep doing what your doing, and never let them see you sweat! Sounds like a commercial doesn't it. Most of the time people will rattle your chain just to hear you bark. Just keep purring!
By going to the principal about staff, I think that you are just opening yourself up for a bad rap that might also cause some bad outcomes in the future. But if on the other had you discretely handle it with the principal witout looking like a tattle tale then it might be more beneficial.
Just my thought. Seems to work for me, but may not work for you.