It's governments that tend to declare war and kill people.
That's just one example off the top of my head. There are countless others involving corporations killing people either directly or indirectly in the pursuit of profits. And that's before you start looking at human rights violations, ecological damage, overthrowing of sovereign governments around the world...
But I'm more interested in this framing. Are you saying that tobacco companies are somehow less responsible for their actions because the government didn't stop them from killing their customers? If the government just didn't exist, and tobacco companies could do whatever they wanted, do you think there would be less deaths from cigarettes?