What if for example they get conned into spending their life savings on fake treatments that exist today and then have nothing left when a promising legitimate treatment is developed six months from now?
And what about their heirs? What if they get conned into wasting away wealth that they could have passed down based on a false idea that it could help them be cured?
Not to mention that it hurts society as a whole to allow money to flow to grifters whether or not the subjects of the con successfully get false hope out of it.