Why are Bees so Important?

I know bees are important, but Why?  As I continue to research and learn about Bees and the garden I am beginning to understand the "why."

According to Ready Magazine:
"Bees are important to the production of fruits and vegetables. The honey produced by bees have important medicinal uses and is a good replacement for sugar as a sweetener. A healthy bee hive is also an indication of a healthy environment. The beekeepers that I speak to talk about a spiritual connection with the bees and the enjoyment that get for caring for them. That is why bees are important."

That's a pretty simple and straight forward answer.  However, this raises yet another questions. If bee hives are an indication of a healthy environment, what does Colony Collapse Disorder (CCD) mean to our own environment?