Is there a rule I don't know about stockings the day of the wedding?

My mom is insisting on buying me thigh highs to attach to my corset for the day of the wedding. I told her I dont want to wear pantyhose that day. She's like 'well what are you going to wear than?' I said 'Nothing'. So she is all bent out of shape about my legs showing in pictures. For no particular reason. She just thinks it looks terrible to show your legs and not white pantyhose in the pictures.

I don't get what the big deal is