It's been very common around here to see a child (and I say child because the boys and girls both do or have done this) walk by first with a baby doll (or stuffed animal) shoved under their shirt, that when "born" is held to their chests to "feed." My kids see nothing weird about breastfeeding their dolls and toys. It's how babies get fed around here.
And I think it is not only just fine, it's also pretty darn adorable.
Now there is a breastfeeding baby doll on the market. You'd think I'd want to run right out and get one for my breastfeeding little Nipple Nazis, huh?
I think it is one of the stupidest things I have ever seen. Not because I think it "promotes the sexualisation of young girls."
Girls (and boys) play house. They pretend to have babies. They feed their babies. Duh. No big whoop. No "sexualization" there.
Both the feeding of infants at the breast and the playing of "mama" with dolls are perfectly natural. What is most ridiculous about this toy is how unnatural it is. Why would anyone need/want to pay for a battery powered, sucking, mewling infant doll? If you want to promote breastfeeding, nurse around children so they think it is normal. Give them a rag doll and see what they do with it.
The doll isn't going to warp any little girls that get it, but it sure would be expensive, annoying and stupid.