This is what we do on our Epson 10600:
We lay down 2-4 empty rolls on the floor perpendicular to the printer, and have a rack that we roll up the slack every half hour or so. No problem if the vinyl get to the rolls, as they keep 'em off the floor, can have a yard or 2 on them, folds nicely.
Good idea with the rotissery though, but use an arm with a microswitch under the middle of the roll, when the vinyl pushes down the arm, the motor starts and runs untill the slack is taken up. Same system on the old Summa Durachrome we have.