A few years ago, I was testing some VoIP equipment for a company. There was phone number assigned to me that had no connection to anything aside from the company involved. During this time, I called the NRA membership department about something just once using that line. A few weeks later, I got a call soliciting money from the NRA asking for me by name. Then another. Then another. I'd never given out the phone number and certainly not asked that my membership be updated with it. I asked how they got that number. The caller had no idea, of course. Oddly, instead of calling my usual number that was associated with my membership, somehow (through ANI, no doubt) they had associated a number from a single call to them with my membership and added it to their solicitation list.
Not much would surprise me after that.