Being a happily engaged straight woman myself, I don't make it a practice to stare at women's chestal regions.
Ergo, when I notice a woman breastfeeding, she is doing it in such a way as to call attention to herself . . . otherwise, I would not notice. I have no doubt I pass a nursing mother every week and do NOT notice.
It's the women who make sure I notice to whom I object vehemently, loudly, and stridently.
Have any trouble getting people to go out in public with you? LOL