I had one of those quilted skirts in the early 70's.
(and lived to tell)
Same here! Naggie has another dress that is a clone of what I had, a window pane print, that is not check or plaid, and I forget what they were called. I was absolutely thrilled my quilt skirt for a short time.
My guess is that Grayson occasionally used her own clothing. I'm sure that her contract didn't include getting any. However, it would not have been unusual for a star of Bennett's caliber to have it written in her contract that she could have her wardrobe. I imagine she quickly snagged the better ones.
Personally, I've never agreed that Vicky looked bad in the sleeveless dresses. I think they worked better on her than the frump cardigan/skirt sets and she doesn't seem like the type for fussier styles either.
All in all, the show is a time warp back to my youth. Yes, we really DID dress like that and we thought we looked good! (Of course, when you are young enough anything looks better. Given that criteria, it is a wonder Joan and Grayson look as good as they do.)