they did not get on your macbook, could be the way your contact list sync was setup between your old phone and the macbook.
I got a new iPhone Plus a week or so ago from US Cellular. The people there took my old flip phone and said they would transfer my info to the new phone. (They did not do this in my presence.) I later checked and found a list of my MacBook contacts on the phone.... I'm thinking, wow, this is cool. Went back to my Mac Book and find the contacts there are gone! I am away from home now and can't go to the store until I return, but HOW did they get into my home computer from the store??? I know there is a way I probably can download or restore them from one of my backups, but, that's not the point.....Any thoughts?
Thanks, Old Granny Lola