There is also a lot to be said about what is "enough" and who decides what is "enough".
I am not even 30 yet, so my childhood was not really that long ago in terms of the economy. My dad supported a wife and eight children on a salary that for the last ten years or so has been touted as impossible for a family of four to live on. The house was always well-kept and the roof never leaked, we ate plenty of good, healthy food, wore clothes and shoes without holes, drove in used but reliable vehicles, and had toys, books, and even some vacations.
We never used food stamps or any government assistance programs, but I discovered in my college economics class that my family qualified for over $500/month in food stamps, even after my dad's substantial salary jump that occurred in my early teens. I never felt and still don't feel like my family should have been considered poor when I was growing up just because we all couldn't do sports or take dance or receive cars for our 16th birthdays from our parents.
For what it's worth, I put myself through college working $8-9.50/hour jobs, came out with $14.5k of loans with my BA, and paid off all but $2k of those loans within 3 years of graduating while working for $13/hr or less - while also saving up and paying for my pilot's license. This was in the Midwest, so less expensive, but I still paid room and board to my parents every month (1/3 my monthly wage). I also bought myself two beater cars during this timeframe as well - both of which were reliable but not very pretty.
Even now,
@2-Bit Speed and I live quite nicely on what is considered by many to be a "barely making ends meet" salary. We own our own house, own two cars outright, we have two cats and a baby on the way, and don't have to carry any consumer debt to keep the checks from bouncing at the end of the month. I would consider our lifestyle very moderately frugal. I shop sales at the grocery store, but we will pick up BBQ or go out to eat once or twice a month and buy new clothes when we need them. I never have to worry about which bill to pay when because there is always enough money in the account to cover all the bills. I would consider our lifestyle to be solidly middle class.
Somehow designer clothes, a Disney vacation every year, and eating out once or twice a week became the norm for "middle class" families. While I agree that the ever-rising inflation and the decreasing buying power of a dollar are factors in the struggle to maintain a middle class lifestyle, I also think peoples' ideas of what middle class living actually is have tended toward the luxurious side of things for a while now.