You're a little harsher than I would be but you make a good point. The problem with online reputation on this type of system is most people won't verify the answers before they upvote them. At the same time an insular community creates a competition for status. So you get people who try to find and answer questions as quickly as possible regardless of whether the answer is right or not.

As someone who goes to Stack Overflow regularly I see this situation all the time. It goes like this...

1. Person asks a question (e.g. "I need to build a service that will serve school districts in Los Angeles County. How do I go about doing that?")

2. Someone comes along and answers the question with something that seems right (e.g. "Here are a bunch of links on building REST services...")

3. That answer gets upvoted and the answerer gets his reputation boosted

4. Later someone comes along with the right answer (e.g. LA Unified requires all services to be WSDL discoverable so you need to look at SOAP"). But it's too late because the question's already scrolled into the abyss.

So the guy who gave the wrong answer gets a better reputation and the guy who got the right one gets nothing (and the person who asked the question likely took the upvoted answer and didn't check back so they waist untold hours on the wrong thing)