Their is a foreign trained dentist in my neighborhood who likes to "overtreat". One of my friends went to him for a small one surface filling, and he tried to sell him on a pressed ceramic crown, and then proceeded to tell him that he required fillings in 6 other teeth (confirmed by another dentist to be completely unnecessary). Keep in mind, this was the same dentist who had pulped out on another friend of mine while doing a simple filling.....he ended up doing the root canal and pocketing the money for that as well. What a jerk.
It harms a practice when your patients are receiving $10,000 treatment plans from some dentist and they simply cannot afford it. So then they go to another local dentist, who takes a more conservative approach and informs the patient of all the unnecessary work that the previous dentist wanted to do. This is not uncommon, and it only ends up giving you a bad reputation as a dentist, and drives patients away.