It will be interesting to see what happens. Some games are very costly to produce, so that may be a factor (in the same way that the argument might not run exactly parallel for big blockbuster movies either).
It may be that we see more variation in pricing, with prices reflecting the cost of production a bit more closely (there are already tiers now for A-list games, budget games etc.).
At the moment, digital is frequently more expensive than physical retail, even for new copies of a game (unless you get a good digital sale).