Computer : In general, most people use a computer to copy the data on the USB drive but it can copy only 1 pc at a time and so it is time consuming. Besides, there is risk of it being infected by computer viruses.
Using a duplicator can swiftly copy from a USB drive to another or many more USB drives. Just have to turn on the machine, and insert the USB drives, and then press ok and the copy starts. There is no need to wait for the machine to start or install a software. It is also virus-free.