Peanuts are nutritious and especially good for farming. It is a perfect rotation crop due to its ability to fix nitrogen into the soil (which is why scientists like George Washington Carver promoted uses for peanuts to expand the market--such as peanut butter).
Netflix's Rotten does a great episode on peanuts and allergies. It explores the problem and suggests one of the biggest factors (beyond the other theories floated) is lack of exposure in early years. Some criticize this, but to be fair to Rotten it did address the other factors noted.
Reminds me of George Carlin commenting how as a kid he used to swim in the Hudson River. This is back when the city dumped its sewage untreated into the Hudson River. What doesn't kill you makes you stronger.
It goes without saying if you are going to have your infant start eating peanuts, shellfish, and other allergenic foods (especially if those allergies run in your family) you should probably discuss this with a pediatrician or allergist first. They may not know a lot on the subject, but it might make you feel better.