It's like having $100. If you give everyone in America an extra $100, the value of your $100 declines because there's more money floating around.
No - education is not a limited resource being divided up among the population (like the work being represented by money). It is like an mp3. You can overpay, not like the song, but its value is dependent entirely on you - how you appreciate it, how you use it.
Start by getting a degree that YOU value, and you'll use it to make your life better. It might mean more money, but it also might mean a more fulfilled life.
interlard - vt., to intersperse; diversify -- Webster's New World Dictionary Of The American Language