It was meant to be purple originally on the inside of the cape, and it looked great in most shots, but editorial felt, I gather, that it muddied her profile a little in the scenes where the images are smaller. I think they liked the idea of some characters “owning” a color, Batwoman and Nightwing with the red and black, Batgirl with the black and yellow, et cetera. So they asked for it to be changed to solid yellow on the interior.
As for the high heels, that’s baffling. She never has them in her own book and shouldn’t have them elsewhere…I guess my thinking is, what girl has only one pair of shoes? ;)