A license fee would be great for the nrl if they can get it and is what they want, but let's not pretend an 18th club doesn't contribute without it. It has never happened before in the nrl.
With what the WA gov are looking to provide to secure a team, then it is fair to say that rugby league will be getting paid.
For example, an upgrade to perth oval and a high performance centre to be used by the team and to support junior development in the state is 100's of millions in direct benefit to rugby league already. That to me is more valuable than say a 20M fee that the clubs will gobble up and waste.
Then throw in the potential for higher value sponsorships for the nrl and other clubs with wider national exposure (has been cited as a reason afl can charge more for sponsors), then the increase in tv rights for a 9th game which is how a new team has traditionally 'paid' its way in.