Except "high fructose corn syrup" doesn't really have that high of a concentration of fructose. Standard corn syrup and most fruits have glucose and fructose in a ratio that's roughly 50:50. HFCS is about 55:45 in favor of fructose, mostly because both sugars are roughly the same stability from a chemical sense, so the enzyme that is used to convert one to the other (glucofructoisomerase, IIRC) can't really get that far from that 50:50 ratio. There are lots of natural sources that are way higher in fructose (agave nectar is like 90:10 fructose, again IIRC).

And fructose isn't added to everything because the sugar is cheaper than other sugars (although the government subsidies for corn farmers do make HFCS ridiculously cheap); it's because our taste buds perceive fructose as sweeter than a similar amount of other simple sugars. So it's actually cheaper to use HFCS than raw corn syrup or other sugar sources, because your actually need less sugar to get the same taste. It's really similar to how artificial sweeteners work; a synthetic molecule can trick our taste buds into sending signals to the brain that say "this is sweet" at a rate that's 80-300x more effective per molecule. A lot of artificial sweeteners do actually have calories when digested, but such a small amount of sweetener gets used that the caloric content gets rounded down to zero. But I digress.

The real issue is that simple sugars are being added in large amounts to EVERYTHING (because they taste good), and processed and prepackaged foods are cheaper to buy and easier than preparing food yourself. HFCS ships easily, has a long shelf life, and puts money in the pockets of corporate farms that prefer to grow one (maybe two) crops over vast swathes of land in the US, which is why it's everywhere. Not that corn is anything special! You can make a high fructose syrup from nearly any starchy crop. Corn was just in the right place at the right time.

Like with most problems in the US, the real underlying cause is the corporations and government subsidies that ignore sustainability (economic and environmental), as well as the health of the population in favor of profit. Unfortunately, that's a tougher problem to solve and political and economic reform is a tougher sell for Middle America than making one specific ingredient into a Boogeyman.

Thank you for coming to my TED Talk.

Edit: cleaned up autocorrect typos and grammar