When I think of these issues I tend to think of them as being rooted most deeply in man's conception of his idealized self as opposed to his perception of nature.
Perhaps we look down upon utilizing chemistry to degrade one's self or cheat in 'battle' because doing so moves us farther from what is generally agreed to be the human ideal?
Whereas we have been raised to understand that nature is primarily a source for raw materials and commodities capable of furthering human goals and development. With ourselves as the center of our understanding and "Human Progress" as our primary goal, many undesirable things can be justified. If we had all been raised on the ideal that a dense and complex interdependence between man and nature was the ideal towards which we
should strive, our society would have grown and structured itself differently.
Moving down from the philosophical realm...
It will be hard to fully vilify all the nasty chemistry that goes into our modern system of food productions, simply because the population at large has been sold on the lie that the status quo (with all it's drawbacks) is the only viable option to produce food on the scale it needs to be produced. Even if people know it is 'evil', they will still accept it because they have not been presented with any alternative that seems viable.
So whereas Lance Armstrong needs only one screwup to fall from his image of impossible superhuman grace, the agro-chemical industry can churn out disaster after disaster and still remain firmly entrenched as a "necessary evil" until an alternative becomes widely understood.