I used to hear it stated like this. In the NFL, you run to set up the pass. If your RB is churning up yards on the ground, the safeties had to play closer to the line to stop him, opening up the big plays. In the CFL, you pass to set up the run, where getting a big lead and forcing CBs and LBs to drop into coverage is the easiest way to give your RB space.
Now, maybe that statement isn't so accurate anymore now that the NFL has become more of a pass first league, but I think it helps explain how the running game and the passing game can work together. In the CFL I don't think you can rely on a strong RB to win you games, but saying it's meaningless is a big overstatement, especially when the weather gets cold.