I wonder if lawyers and physicians have similar "insightful contributions" from non-expert amateurs. Do people just wander into their offices and offer free advice on how to go about their work?
As a matter of fact, they do. It's actually a common complaint about doctors -- especially family doctors -- having to argue with the know-it-all parents of their patients. The debate often goes something like
Doc: "Your son's getting these headaches and throwing up because has a viral infection. He'll be contagious, so you'll need to keep him home from school and give him lots of rest."
Mom: "Oh, really? I looked up his symptoms on WebMD, it seems to me he's having some kind of allergic reaction. I'm thinking he has a gluten allergy."
Doc: "Based on what you've told me and the tests we've done, it's very unlikely this is an allergic reaction."
Mom: "You didn't test him for gluten allergies. How can you be so sure?"
Doc: "You're right, I only spent fifteen years in medical school and then another ten years practicing family medicine, so clearly your twelve and a half minutes reading WebMD makes YOU the expert on childhood pathologies."