Well, like I said, it's a spectrum. And as you walk on the spectrum, a point comes when the misery contributed due to your actions is too insignificant, or too indirect to take any direct responsibility.
The idea is to not reach the end of the spectrum, but to move on it. Progress is the goal, not perfection.
About the clothes, there are people all over the world who have started to boycott companies like hnm because they pay their workers very less. I think that's because hnm promised that by now, they'll start compensating fairly, but they haven't, and that is why people are mad. I'd say that's an example of moving on the spectrum.
Coming to owning a tobacco company, if I'm being blunt, I'd argue that they are forcing people to buy cigarettes. Not directly of course, but let me elaborate.
Research has shown that we are products of our environments. In a study, when a cafe replaced soft drinks with water from the display, it's sales dropped. Mind you, they were still on the menu, but just not in direct sight of the customers. And when they put soft drinks back on the shelves, it's sales increased. Meaning, the cafe owner could influence whether or not people make healthy choices just by changing their environment. Here, one could argue that it's still the customer's choice to not order a soft drink. I agree, but very few in our society have the mental toughness to make correct choices all the time.
The concept of taking control of your life is good on an individual level, but if you want to improve the lives of the masses, you have a better chance of doing that by changing the environment.
Also, think about the obesity pandemic in countries like America. It started after the fast food chains boomed. It's not that the current generations are lazier, and hence obesity is higher. It's just that the current environment favors obesity.
So while the final choice always rests with the customer, by making the environment worse, they make it very hard for the customer to make the right choice. I won't use that as an excuse to lose control over my own life, but when you talk about millions of people, I don't believe they're in a place to have total control of their lives.
Yes, smokers choose their own misery, but I do believe that some of the blame falls on the people who sell tobacco as well.