For some people, the mere fact that what they're working on produces joy rather than ??? is worth the pay/security difference, even if the everyday work itself is nearly the same.
I can imagine quite a few benefits, to be honest. You get to work with other people who decided to make the same sacrifice, meaning you have something more in common with your coworkers through your work than just picking the highest paying job. You get to say "I did this" and point to a part of a game that potentially millions of people are playing.
If I were evaluating two otherwise equal jobs, I could see myself taking a $5k or maybe even $10k lower salary for those kinds of benefits. The cost is much higher, though, (in terms of salary, job security, and overtime requirement) which is why I've never worked for a game company and probably won't in the future.
