Wait, what? Game development seemed like the most stressful/worst thing you can do in software, i'd never expect game developers to make less than average developer.
Game Developer Magazine runs a salary survey every year. The average game programmer salary in 2012 was a little north of $90,000. There are game programmers who make much more than that, but it is not the norm.
It's a supply and demand thing. Very few people grow up wanting to make web apps, but many many people grow up wanting to make games, and when they have that chance, willing to take a pay cut to do it.