Got charged $100 for "dental hygiene training" during annual dentist visit after dentist walked in and asked "Do you floss?" - "Yes." - "Good. Floss every day." and walked out. I only know of this charge because insurance refused to pay and they sent the bill to me. I know it's definitely about these two utterances because this was the only interaction I had with this doctor at all. Everything else was performed by dental students.
I now refuse to answer any questions that do not directly pertain to the immediate procedure.