I just have to add as a postscript to this (my kids are having a rough adjustment to the school year, I guess!) I was with my DD's teacher yesterday for another event and she needed to speak to me about a minor behavior issue. Polar opposite approach. She said something like, "Hey, so I'm having X issue with DD in class. It's not really a huge deal, but I don't want it to continue because Y good reason. Do you have any ideas on how to best handle it, or what might be going on?"
That is how you approach something like this when you know what you're doing.
In this particular case, maybe just explaining the whole "different situation, different rules" would help?
yeah, and maybe we haven't emphasized this enough.
But I do think this is a "bad impression" situation. I mean, we all know it happens. DD had a teacher last year with this reputation. For whatever reason, she was a darling of this teacher and could do no wrong, while other children got a lot of flak. Even she knew that it was sort of unearned.