this is how it works,
send in a sacrifice voter to take an original ballot(s) when they vote.
They then take it out to the precinct boss waiting across the street.
The form is filled out, and given to the next voter who goes across the street, gets in line and returns with the next blank ballot (and gets paid)
The process is repeated. The stooge is not paid untill the ballot is returrned blank. Only the precinct boss fills out ballots.
Are you saying they are stacks of blank ballots accessible to the voters walking in the door such that they can grab one or more extras? We don’t have that here. The ballots are controlled by the poll workers. Or are you saying the poll worker gives the crooked “voter” an extra ballot? There has to be an extra ballot each time or there’s no advancement of the numbers. You’d also have to have a complicit poll worker or two, which wouldn’t be hard to do, but that’s not what you described. If there are stacks of fresh ballots sitting around, anybody could go to court and shut that down in minutes because no jurisdiction would not have rules that control that strictly and carefully.
So what you’re describing doesn’t seem to make sense in terms of increasing the numbers for the cheaters. I think the absentee ballot/mystery registrant is the major means by which they cheat.