I think the reason that she still wears these old, worn out leggings isn't that she can't find anything that fits her, it's that she genuinely sees no problem with the whole affair. Now, obviously she's not going to be able to walk in to any random store in Bumfuck, KY and find dainty gorl sized leggings, but the internet is a magical place and she's technologically savvy/fiscally able enough to make it happen. I think she's just a nasty bitch and has no problem wearing stretched out leggings with holes that you know get washed maybe once a month.