It's called contact tracing and it's a lot easier when you have many sources doing it as opposed to spending a lot of money hiring people to track it all down after the fact.
I've avoided my family and friends for seven plus weeks now. I go to the neighborhood grocery store or drug store maybe twice a week. My family has ordered takeout once a week on every Friday night. I've been compliant as fork. I'm an outright socialist on the political board. But entering my name on a login sheet at forking Walgreens so that can be passed along to the authorities is a bit much for me to accept.