Why would a new player need to buy during the presale? The presale packs cant even be opened till the official release which is over a month from now. Also the presale is only 1 million packs of the 15 million to be sold so it isnt like new players wont be able to buy later.

Vouchers are also going to be used for other events, releases, etc etc so if you dont have many you could save them till the next thing that will take vouchers. While CL packs are $4 the next thing might be worth $30.