Response to "Belief and what we realistically do"

First of all... There are two answers, the one that we want to hear, and the one that is the main answers, and that's not that easy to hear.

I'm not a philosopher, but I'll try to explain it.

Fast food restaurant: The person in charge are able to bring changes for the better. He/she can try to introduce healthier food such as salad to the menu, can try to fund a research on how to cut down the cholesterol in their making of hamburger, etc. But, it's still the consumer who pick and choose what they want. They can either choose to eat salad or eat French fries every day from the exact same fast food chain.

Soft drink company: Do you know that Coke used to have cocaine in their main ingredient? It changes, for the better, right? We all know that soft drink is bad for us, that's why all these soft drink company tries its best to cut down sugar, or this and that... so that the consumer who are health conscious would buy the diet one and such and such..

Liquor is the light of people's party. People who drinks moderately enjoy the taste of liquor and love to have em since it brings joy and laughter to the whole company. Even Jesus drinks wine and have party here and there, right? Liquor becomes dangerous when we consume it excessively. It's as simple as this. Do we want to be controlled by things? Imagine being controlled by a trash can. That's what happen when alcohol controls one life. Our life is being controlled by an object. It all goes back to one's choice.

"If you are a chemical engineer working in a herbicide-producing plant, should you feel the responsibility of decreasing quality of soil though what you're doing makes sure millions of people can eat each day?"

That's probably the main question, isn't it?

My answer will be analogous to the fast food answer.
This question was brought up in one of our classroom discussion about "ethics".
One side argues that it's not ok to work in the field where you're strongly opposed to it, in that case, in a pesticide company.
The other side argues, "we need to pay our bills".
Moreover, the other side argues if one have a good background in pesticide and such, one can bring in positive ideas and even make the pesticide that they're making better for the environment. That'll bring the rating of the pesticide they're making up, that'll bring a healthier environment, and such and such.
And even that, the consumer may still opt to not buy the pesticide.

So, the main answer is, "our conscience along with our 'free will' will dictate on how we look at this problem."