Because you dont have written permission, as an individual to use their logos. EA has an agreement. This is where the conflict lies. In order for you as an individual to create a mask using an NHL logo. EA would have to adopt that permission in their contract with the NHLPA. And its highly unlikely that, that will take place. Masks are in a different realm than team equipment. Sweaters, socks etc. Masks are personal property of NHL goalies, and are created by the player and designer. Permission for use of those lie with the aforementioned. If you were to go to a sports shop dealing in mask design, and asked to have a mask made like Montembault for example. He would be unable to do it. It is copy righted.