
This was taken at the zoo when DD was about 3 months old, or so. It's not always obvious that a baby is eating when they're snuggled up in a sling

I know what's happening in this picture, but DH was standing on the bench behind me, trying to get DD's face in the shot. He didn't know that DD was eating before he went for the shot.
OTHO, when I'm at home I have been known to take my shirt off entirely. Obviously I wouldn't ever do that in public, or if I had people over. After BFing 4 babies, I've gotten pretty good at nursing discreetly. I typically wear a nursing tank/cami under my shirt, then the shirt comes up, the tank comes down, and there's very little exposed.
I have nursed Baby several times in stores. I plop DD in the shopping cart seat to contain her, then hold Baby across my body, laying him across the handle of the cart so i can still steer the dang thing.
My feeling is that my baby needs to eat. I am going to take care of my child's needs, but that doesn't mean I call attention to myself or make a big production about it. Pretty much the only place I won't BF is someone else's house, if they're at all uncomfortable with it. My experience in this regard is unique in that I don't have many friends who aren't also family. And most of my non-family friends are either super old, I've known them forever, friends, or else they're also moms who tend to share my viewpoints on the subject. Either way I know their feelings. So at Dad's I'll excuse myself to the other room, if I'm at BIL 3's place for some reason, it's time to go home.
As for sounds, my kids have made similar sucking/gurgling/gaspy noises with either breast or bottle. Or at least, I perceived them to be the same