I don't know how many people are partaking in this ballot, but even with a small number of people it's much less economically feasible to individually travel to and pressure people at their homes versus having a set number of places you can arm with your "political guard."
Except that the set number of places have monitors from both sides who can prevent anyone from having to show their ballot in the 30 seconds between when they fill it out and when they put it into the box.
