Even as a SAHM you will very likely be going out in public and may need to feed. I was a working mom but still went out to lunches and such with a SAHM friend of mine weekly, plus we had little play dates and took the kids to the park. I can tell you her and I bf'd in public equal amounts if not her more.
Ultimately it just depends on how modest you are. I am not modest at all and could care less who sees what on my body, so I just flat out nursed where ever/whenever my kid needed. (I also was always borderline ready to start a bar fight with anyone that gave me a hard time but no one ever said anything lol.) I did wear a nursing tank top and just lift my shirt so really I was completely covered, but I never found the need to cover my child's head while she nursed. If you looked at me it just looked like I had a kid to my boob-no skin really showed.
I did know a few moms though that needed the nursing cover to keep their kid latched though which sort of made me laugh. If the child wasn't covered they would get distracted and try to look around while nursing so the mom had to cover their kid to make them focus. I never had that problem-my kid would nurse constantly if I let her so I had no experience like that. :)