The point stands. How many people consciously make an effort to prevent cancer in every aspect possible? On a personal level as much as a societal level, we're doing little to address the preventable causes of cancer. Why are so many people making so many "bad life choices"?
The wikipedia article on capsaicin links to this study as well as several others and indicates that capsaicin may have carcinogenic or anticarcinogenic properties based on several studies: http://en.wikipedia.org/wiki/Capsaicin#Effects_of_dietary_co...
You probably shouldn't be all that concerned about eating spicy food... on the other hand, if you don't smoke, you eat well, and you aren't obese, you're roughly 55-65% less likely to die of cancer: http://en.wikipedia.org/wiki/Cancer#Causes
Unhealthy eating (especially very salty/spicy/fermented foods), alcohol use, and so on also classify as environmental factors. But they are not caused by pollution or chemical-laden foods, merely bad life choices. Copious quantities of red meat isn't good, organic or no.
I don't meant to imply our bad handling of the planet causes no cancer, it certainly does. But it does not cause anywhere close to 90% of cancer cases. Not by a long shot.