To counter this, a lot of dentists use phrases like "pain free" in their ad collateral, and include all kinds of joyful imagery in their offices.
The only problem I've had with my dentist, and it is such a minor quibble that is hardly worth mentioning (except that it is on-topic), is that after every appointment they try to sign me up for wisdom tooth extraction. I'm over 50 and have never had problems with my wisdoms - even the x-rays show them as being perfectly fine. Maybe harder to reach, but they're still clean and healthy anyway. So I just say "No thanks" and schedule my next appointment.
I think my hygienist has an awesome personality, so I don't give her any flack for trying to bring more money into the clinic.
Yeah, I would say that good 20% of posts are about anxiety of dentist visits. But what I've seen many more stories about over-treatments. Luckily for you, your dentist didn't abuse your trust.
So I'm inclined to believe those stories. I just accept that dentists make more money from wisdom extractions, even if there's no reason to have the procedure. It only annoyed me the first few times until I realized they'll always be asking me this.
Incidentally, I think it's a lot like circumcision. A lot of natal doctors just assume they're going to be doing that without asking the parents. It's mostly done because it's a surgical (read: more money) procedure to add to the medical bill. It's pretty much illegal to cut without specific permission where I live now, but that was a common complaint before then.