From previous reading on the place, it seems a certain religious / ethnic sect used it (Persian refugees of Christian faith) and they perhaps used it based on t

From previous reading on the place, it seems a certain religious / ethnic sect used it (Persian refugees of Christian faith) and they perhaps used it based on their experience with having their assets seized by the Iranian regime before they fled. It’s a bit tricky since a number of the deposit boxes were directly connected to actual crimes but I believe that’s how they became popular in the first place.