It would've been easier and quicker if they could just come in guns blazing. Alas, that wasn't the safest route for them or the girls. Noise would draw attention. So each person Vegas snuck behind was silenced with ruthless efficiency: a hand over the mouth and one quick, deep cut to sever the vocal cords... as everything else in the way of them. It was moving the bodies to a place where the blood wouldn't seep into view that took the bulk of the time. They had time as long as they remained undetected.