I am thinking that she would exchange it before she has the baby. She seems in the mind set that she doesen't need one. She prob. read or heard something about not wasting you money on a boppy becasuse you can just use a pillow. I personally did not use mine very much. My DS would scream bloddy murder if you took any amount of time getting him to the breast. I was always fumbling with the Boppy. He hated tummy time so it did not work for that. I used it a couple of times to prop. his swaddled body when he was a newborn but the Infant to Toddler Rocker I got, worked so much better for that. My sister on the other hand could not live without the Boppy.
It's up to you but she may just return it right away. She can always go back and get one once she has the baby. The Infant to Toddler Rocker by Fisher Price is my favorite gift to give. You can put it like a bassinet when they are newborns and then it switches to a bouncy style seat when they are ready for that. When they are older it can be used as a rocking chair. Just an FYI. I also love the Baby Bjorn plastic bibs with the big cup at the bottom to catch food. I can't figure out how moms live with out it.

Maybe you could lend her your Bobby so that she could try it out.Then you are not buying her a gift she doesn't think she needs but she gets to try it out.