I should add, the recent Indian BT scams did know 'my' name, or at last, that of better half. Which merely supports that she has in the past been inclined to sign up to supermarket loyalty cards and the likes, with their famously (but legal) privacy leaks.
Similarly, many hotel booking sites, as well as social media stores, when you read small print on (say) page 45 out of 86 if their T&C, reveal they reserve the right to pass on details to whoever they like, whenever they like.
I am sure it is that leaked/mined data that goes into the great big pool from which the scammers make their calls, selected at random.