They should be looking at sell outs in big city stadiums for the (presumably) the two semi-finals and final, no less. The other games, I wish people would get out to see them, but if we are expecting big full houses for (no offence) France v PNG, then we might be dreaming?
There are opportunities for good crowds though in the pool matches, especially the games in which Australia and New Zealand compete. It depends how they target the locations and stadium sizes for these matches, whether the interest is to fairly spread the games across locations, or the main interest is to make sure there are no financial losses this time.
For example, you could possibly look at a 20,000 full house at (for example) Parra Stadium for an Aus or NZ (or England?) pool game, compared to the risk of not filling a bigger capacity ground (and having increased costs vs unfulfilled income as a result). Some grounds cost more to hire than others, this has to all be factored into the sums. Pool games not involving the bigger countries will draw smaller live crowds, and should be played in smaller (cheaper) venues and locations.
This can't afford to lose money, two WCs in a row in the red would be a disaster. They need to build expectations around the series to make sure they get as much as they can out of broadcast rights, remembering there are costs to be covered for ten squads and their touring parties.