When my son was born and I had to go on a dairy free diet due to him being allergic to milk (I was breastfeeding) I started to really look at the ingredients in the food I was buying. It really opened my eyes to the kind of junk that I was putting into my body that I thought was healthy but really wasn't.
One of those things was peanut butter. I thought I was being healthy by eating it but the stuff I was buying was not actually peanut butter- the jars always said "peanut butter spread" on them. If you look at the ingredient list on your favorite brand of mainstream peanut butter you will see that there are lots more things than just peanuts in it. Do you really need added oil, sugar or salt? The answer is no. Even the "natural" versions the mainstream brands put out are no better which goes to show you cannot trust the claims on the front of the package and need to look at the ingredients.
I only buy peanut butter that is made of peanuts- nothing else. You know what? It tastes awesome! Peanuts are tasty on their own and don't need any help to be yummy. Whenever you buy the stuff that has added ingredients you are putting unnecessary processed ingredients into your body and really for no good reason at all.
If you are interested in switching to a better diet, with less processed foods and more wholesome foods, then switching the peanut butter you buy is such a simple step. You'll be eating a far superior product and can feel good about feeding it to your kids (and yourself- I like to eat it off a spoon).