HFCS exists ONLY because of US government policy. The US sugar program drives up the price of sugar by limiting domestic supplies and imports. As as result it is profitable to mill corn into sweetener, and U.S. food makers use it as a substitute everywhere possible (mostly liquids) as it is slightly cheaper than sugar.
Soda outside the US,for example, still uses traditional sugar.
As a result, the corn growers are a vociferous lobby in support of the sugar program.