You beat me to the response.
Can you imagine the uproar on this forum in a years time if a plane comes down (god forbid) and the cause is due to damage sustained by flying through ash over the coming days. I can imagine it taking less than 10 posts for someone to blame the authorities for allowing planes to fly.
We're talking about people lives here, and yes it's a great inconvenience to us all, however lets pause for a moment about the pain and loss that would be caused to people if the authorities/airlines got it wrong.
If you look across on the flyertalk forums, it generally full of very frustrated, yet understanding travellers. They'd rather be safe than sorry.