It proliferated in America because of a law in the 1990s called the DSHEA which greatly loosened regulations on what could be sold and advertised. Before then,

It proliferated in America because of a law in the 1990s called the DSHEA which greatly loosened regulations on what could be sold and advertised. Before then, all this was illegal. Once it became legal it became a multi-billion dollar industry. So now even if a politician is against it on moral grounds, they are afraid of harming the economy and eliminating all those jobs.