My son went through that in K4. Except it was all on his own, nobody said anything to make him feel funny. Where he went to preschool, we were supposed to pull up to the portico and a teacher opened the door and "helped" them out of the car and ushered them into the building (there were others inside the doors to assist beyond that point, if needed). It was a very small private preschool.
One day, he asked M. not to kiss him at the door anymore, because he didn't want anyone seeing (his teacher, I think... a little crush maybe?) Anyway, there was usually a few cars in line that we had to wait in, and he asked if I would kiss him BEFORE we got to the door.
So maybe, since your daughter may still LIKE the kisses, but not like the attention about it from others, you might ask her if she would like you to give her her morning kiss before you get there. ?
My son is 13 now and still LOVES big hugs. He is very affectionate. But he prefers to only hug when no one else (in public) can see. ;)