If I can find out who they are, I will sue their [***] off. My number is a cell phone, known only by my very elderly parents, but clearly now someone else. They called me in traffic! My Cerebral Palsy makes it life threatening to try and answer on the road.
Based on all of these posts, I am gathering here that there is no possible financial gain made by this source making these calls, as the source does not request any personal financial information, nor does it want to sell you anything, as it never tries to and won't let you call back. The questions are random, so their purpose seems only to keep you on the line. Despite the large and widespread number of calls being made and reported, the source is not being shut down, even though an average person can locate the source on a map using code search engines.
So I'm guessing the purpose is to test tracing and possibly even location technology using your phone signal, or something along those lines.