Me too. I have a facebook@mydomain email address that I only use to log into Facebook and my "advertisers who use a contact list" has all those same car dealerships (and no other advertisers). There must be one company that paid Facebook for email addresses and then resold them to auto dealerships.

It could be some third party ad firm trying to generate "lookalike" audiences. They could run some algorithm on their random email lists based on known customers, then upload the resulting list to Facebook.