More commonly each person has a different style piercing in mind, but we do have groups that have the same piercing in mind.
If one person is unsure of what piercing they want, they sometimes get the same piercing as their friend. The friend many times encourages them to share in the same piercing experience.
This photo is of two girls that have been friends since childhood. One girl was going to get a Monroe piercing, but decided to get the same piercing as her friend.