The only reason I ask is that previously the TO's have ruled the other way. One time the tournament rule was that your deck could only use either permanents, creatures, or spells (Pillar and Pends excluded, of course). In that tournament Graveyard was banned because it was capable of creating illegal cards. But as long as the rules are clear, I'm happy to play these rules (because I have a Nymph Queen )
General praxis is that bans pertain only to deckbuilding. You may normally create banned cards through means of others (FFQ making Fireflies, for instance). Sometimes, to preserve the theme or balance of a tournament, more bans are required.
