Stroppy, my point really is that, whether you, I or anyone else feels it necessary or not, something like this can be very enabling for some women.
We can't know this particular woman's reasons for wanting to cover up so it's pointless to speculate on that, but I do know from experience that it's not necessarily society's prejudices which makes women feel self-conscious about their bodies or about breastfeeding in public.
My norks were 48KK when I was feeding; I would defy anyone to try and be discreet or uninhibited whilst a baby was grappling with those! I chose to cover up with a scarf, and I was perfectly happy with that. I find it confusing that something as simple as a cover-up, which enabled me and others to feed without feeling self-conscious, causes such annoyance in other people.
What would have been the alternative for me - giving a bottle of formula every time I went out? It wasn't going to happen. But if I hadn't been able to cover myself up, maybe I wouldn't have had any choice.
Better to breastfeed in a way which suits the mother than not at all, don't you think? Regardless of her reason for doing so.