It's standard. When my son was born (almost 4 years ago) the pediatrician recommended Poly-vi-sol. "Because breastfed babies tend to have iron deficiencies." So, we tried giving it to him, and he threw up. Consistently. So we stopped. At the next pediatrician appointment, she said she was going to test my son's iron, since we weren't giving the vitamin. It was fine. We have a new pediatrician now, by the way.
So, when my twins were born nearly ten months ago, our lactation consultant (one I didn't like, and she worked for the pediatrician's office) told us that the babies needed a Vitamin D supplement. Made by the same company as Poly-vi-sol. I got some gave it to one of my girls and it seemed she threw up everything she had eaten that day. So, we ditched the vitamin supplements for the kids. At least until they're old enough to have Flintstones.
I take my vitamins, I eat smartly, and the kids are not "shut in" so they get some sun exposure. I am more than a little tired of the medical community defaulting to "breastmilk alone is insufficient." I will admit there are times when some sort of supplementation is needed, but in general, I think the pediatricians just have an innate distrust of breastmilk and its ability to provide all the nutrients a newborn needs.