Skills are like any other commodity. When I was active duty, I was an EOD (Bomb Disposal) tech. I did not get payed much, but I was happy with my job. When I re-enlisted, I signed up for 6 years and was rewarded with a $3000 bonus for doing so. I retired in 1995. Currently, EOD techs typically see in the neighborhood of 80,000 dollars to re-enlist. In addition, they receive all kinds of incentive pays over and above their salary that I did not. Is that "fair"? My skills where the same. My willingness to work was still the same. The difference is that my skills were not in demand at the time. There was no need to offer me incentive pays to continue doing what I did. Now that Afghanistan is winding down, guess what? They are cutting way back on bonuses and incentive pays because those skills are no longer required as much.
At one point, MCSEs and Novell CNEs where getting paid a pretty good amount. Once the market became saturated with them what do you think happened? The market "equalized". Those that were willing to work for what was offered did so. Those that did not had to look elsewhere.