Teach me to generalize from personal experience!
I didn’t find that breastfeeding prevented ear infections, in particular. All my kids had them, including the ones that went longest without eating food, until I started cleaning out their ears with Tea Tree Oil. On the other hand, one of my friends has a daughter with Down Syndrome, and she attributes the avoidance of ear infections (endemic in Downs children because of defects in the ear canal) to breastfeeding.
So, in conclusion, nurse the babies as long as humanly possible! It’s free! And I’ve lost the snake. Oh, dear ...
Well, my oldest was the only one who had a lot of ear infections, and he breastfed for the shortest time and was the only one who used a bottle. I had to stop nursing him because I was pregnant with my second, and I had pre-term labor with my first.