Why, because they supposedly have cyanide in them? It's all a massive confusion.
And are they really 'bitter almonds' or apricot kernels? There's a possibility the two are one and the same.
The supposed 'cyanide' people speak of that is present in apricot kernels and apple/pear seeds, is in fact a compound called amygdalin or vitamin b17. If taken in extremely huge amounts it can make you sick, but it's a myth that it is the same as deadly cyanide.
Cyanocobalamin, the cyanide form of vitamin b12 is a common health food supplement. It is cyanide based but like b17 it is not the same as the deadly cyanide people are thinking of.
Eating bitter almonds / apricot kernels will not kill you. It's just a myth. Some people such as Jason Vale the arm wrestling champion eat massive amounts of amygdalin in apricot kernels to prevent and treat certain cancers.