I've personally known at least five people who have been in a car accident and then received a windfall of cash after paying off their medical bills and having their car repaired/replaced.
I don't know if this is still the case but years ago my friend, who was in a collision with a drunk driver, was told by his attorney that the insurance will just settle for 3x your total expenses (medical, car repairs, etc). He was being encouraged by his attorney to see chiropractors and specialists because of this.