This is because those people create a control group that is the enemy of big pharma and government lies. This became apparent decades ago when doctors realized the Amish were such an unvaccinated control group amongst whom diseases like asthma and seasonal allergies were almost non existant. This was evidence to support claims that childhood vaccines were the cause of all that. The govt response to that was to try to force the Amish to be vaccinated and those that refused were constantly harrassed by health authorities.