Yup. The numbers of games bought vs downloaded is quite a difference. It does pay to be sensible and buy games you know you'll play more than once rather than buying 20-30 games a year and not finish many and $600 U.S pays for a hell of a lot of hardware upgrades.
I know many people who pirate that support this logic. They have 600+GB of pirated games they have never played. I know someone with over 200 burnt Xbox 360 games. How many games did publishers really lose out on? About 5 or 6.
The biggest weapon against piracy is a timely Steam sale. A lot of my pirate friends are very value concious. If they can get a game for $20 they will buy it and take advantage of the convenience of Steam rather than download it.
Tease.