These are people in the community that other parents can go to who might not have the ability to contact you personally. For example, the very first school at which I taught had a high percentage of Spanish speaking parent in the home. Getting these parents to booster meetings was difficult at first due to an intimidation factor over the language barrier. However, I did have a very active parent who also worked at the local bank. I would list her name and number as another contact.
Parent involvement increase quite a bit.
I also believe in spreading the workload around. I have specific committees and descriptions of those committees for parent to read and decide which they will be on. If your student is in band, you must be involved in at least one of the activities listed below. Remember, other parents are helping to support and nurture your child, too. That is a quote from my jobs list.