...I want a statement that autism is created by the Flying Spaghetti Monster. For reasons only He understands, He sometimes reaches out with his noodley appendage and gives kids autism.
Is that true? We don't know, we haven't rigorously investigated it, have we now? Since there's exactly as much evidence to support the FSM as vaccines causing autism, the CDC has a duty to mention both possibilities.
Show me all of the studies that have evaluated the correlation between FSM action and autism. There has been a lot of research on the possibility of a correlation between vaccination and autism, and no evidence of correlation has been found. There is an enormous difference between "We've looked hard and found no connection" (evidence of a negative) and "We haven't looked at all" (lack of evidence).
In addition, there's no need for the CDC to debunk a claims that are not being made, or non-harmful claims. To pick a less-ludicrous example, there's no significant population claiming that eating grapes causes autism, so there's no need for the CDC to address it. Further, if there were an anti-grape lobby touting a connection with autism, the CDC probably still wouldn't need to address it because some people avoiding grapes doesn't create significant health risks to others.
But there is a significant population claiming -- against strong scientific evidence -- that vaccines cause autism, and that claim is causing them to reject vaccines, which does create significant health risks for others. So, the CDC absolutely does need to address it, since public health is their job.
Your analogy is terrible, in every way.