Startlingly, I found that I am therefore in the minority of parents ...
I am partially in this minority too. The importance of keeping herd immunity levels elevated certainly does have a bearing on why I choose to give my child a particular vaccine. It also is a big reason why I myself have had both pertussis and MMR boosters as an adult. Although my decision is based on a combination of both societal reasons and the fact that I personally feel that the benefits of a particular vacc outweigh the risks in most cases.