Mike,
A camera is a tool. Just as a saw or drill is to a carpenter. As with wood, some people only need simple tools to do minor repairs while others build custom furniture. To some, photography is a minor hobby, to others a passion, and to some a business. I agree that not everyone needs, wants, or can afford a 5k camera. When you post JPEGs on this list, Facebook, or anywhere on the web, you cannot really see the level of detail in a high res photo. JPEG was developed so that files could be sent over the web. When JPEG was developed, a lot of folks were still using dial-up modems. JPEG throws away most of the data in a high res file. If all you are doing is the web, then just about any camera would probably work.
I guess it is like anything, golf, fishing, skiing, etc., some people are OK with the basic, simple tools and others need a lot more.