Logging in is important for a few reasons:
1) If you didn't have to log in, then anyone could place orders for your store - and you don't want that!
2) Logging in provides a record for both you and the brand of your activity.
3) Most brands do not want just anyone seeing their upcoming products. Access to the portal is granted only to people who need it - like you! You're special - don't forget it! ;)