Amazon, the dominant book store in the world, goes one better.
It kills them commercially by taking them out of their "everything" store.
Last week, we interviewed a mother who developed a protocol to treat autistic children which has succeeded in curing - not controlling, curing - the disease in over 500 documented cases. Thousands more have been helped.
However, because she mentions vaccinations has a potential contributing cause to autism and other diseases, her book along with other books and films that discuss this issue, has been removed from Amazon's shelves with a vague "violation of community standards" claim.
