We don't necessarily have to be out of control to keep consumption at a normal level. It's just that the second people make a bit of money, it's already gone on a fancy new car or god knows what.
I'll give you an example. I post on an analystforum for people doing their MBA or CFA as well as other finance degrees. There was one guy who posted about a year ago. He said, "Last year, I was making 280 K as an Ibanker but I lost my job due to being involved with one of the big banks (hint Bear) and now I have no money left because I have no job. What do I do?"
How does someone who makes 280 K which is about 5 times my salary go from that much to zero so quickly? How does one not save at all? You don't have to put away 280 K but FFS, put that 100K aside a year and you'll be pretty fine for a rainy day.