In older versions we could change the amount in options.

Example:
someone orders 6x bread so you choose bread and change the amount to 6 than you choose in options what type of color brown or white but you need 2 brown and 4 white. So you have to change the amount within the choosen options.

This method is easier because you dont have to spend and do 6 lines of items on one receipt. Its quicker is more efficient and therefore better voor the environment and your wallet because you need less paper!