I am no expert, but from my reading it seems like 903.11 is a rule for play groups that ARE allowing cards to be brought in from outside of the game considering the leading phrase “if a player is allowed”. It is also possible that 903.11 was written first or was written before some amendment to 10 (if one occurred)
Pirating a software still shows a company that there is interest in it. They will only know they are screwed when people stop buying and stop pirating