You do realize that wages are adjusted for cost of living changes over time? (This is a gross simplification of the actual process, but the fact remains that wages are not constant in the face of inflation.)
Take a look at this please (using median wage here to make this more clear):
http://www.wolframalpha.com/input/?i=all+occupations+median+...
However, here is median wage too: http://www.wolframalpha.com/input/?i=all+occupations+mean+wa...
It is also worth noting that the average wage back in the '70s was roughly $8,000.00.
Edited in Response to Downvoting:
Inflation is caused by rising prices, and wages are one of these prices. Your wage is simply the price of your labor. In the long-run, wages are flexible just like all of the other prices. Admittedly wolfram|alpha does not have extensive historical graphs available, but I am not trying to write a book here.
If you are down-voting because you have not received a pay increase lately, then you should be aware of the fact that wages are usually a bit more sticky than other prices in the short run.
If you are down-voting this, I would appreciate engaging you in honest discussion about the point that I made above.
The parent post said that inflation gives workers a little pay cut every year. Painting this wonderful image of a worker sliding into poverty. This is demonstrably false. Yes, a 1% or a 2% rise in inflation will impact your real earnings, but wages are not a static process and they do reflect the actual costs of living changes that take place over time.
As an economist, I am constantly amazed by how poorly the press discusses inflation and how little most people know about what inflation is and how it interacts with other variables within an economy. Please read this pdf for some discussion on wages and price inflation:
https://www.clevelandfed.org/research/policydis/pd1.PDF
It is an academic piece, but it is one of my favorites for illustrating the interaction between wages and the greater macroeconomy.