It's easy to say you don't care about money when you have money. You can sit around in smug satisfaction thinking that an extra $30,000 a year doesn't add much to your quality of life, even though you know that's a bald-faced lie. Sure, at a certain point, money doesn't buy happiness (someone making $400,000 isn't much different in the happiness department as someone making $350,000), but if you're struggling while making $40K a year, making $50K is going to make all the difference.
One Irish worker got into an awkward situation with his soon-to-be former boss. After finding out he would only get a 5% raise from 32K euros a year to 33.5K (For the Americans in the crowd, that would be a raise from $35,119 to $36,762), he got a new job where the salary was 38K euros. Of course, his boss gave him a hard time about that.