I don't get it either. I try to keep the rules the same for all of my students, not to show favorites - although I do have some that I'll miss more than others at the end of the year and I admit that - but it makes it difficult when situations like this come up.
My mum was a teacher and she always stressed to my brother and I both that we needed to follow our teachers instructions. And if we didn't agree with them, or she didn't agree with them, it would be handled outside of class time. So as not to disrupt.