Yes, when I was pregnant with my first baby, my mother was fully supportive of my desire to breastfeed... in a back room where no one could see.
(I was due about 3 months before Christmas).
I informed her that I would not be stuck in a back room, missing out on all the socializing, just because my baby got hungry. Her reply was, "Well, I would come and sit with you!"
She meant well but... sigh...
Anyway, fast forward that and after that first Christmas went by uneventfully, she has become one of my biggest supporters.
We had another incident like that when dd was about 3. She said that she thought maybe it was time to stop nursing her. I told her that I would stop nursing her when she (dd) and I agreed on it and not before. That was the end of that discussion.
With my second child, she was completely supportive all the way through. And now with my third, everything is just 'normal'.
It's taken my Mom a lot of years to get this comfortable and it's taken me being very strong about it. Funny, my step-Dad and his family (parents) were totally supportive from the beginning and never said a word... but I think it's because his Mom bf'd both him and his two brothers.
It's a familiarity thing... I think.