This actually is a very valid argument. Cigarettes actually provide value to the user. Yes, there are negatives, but the user typically knows those and decides the upside is worth the risk.
Do people know the risks of being profiled by ad companies? I am not sure most people can even begin to understand the associated risk. The few attempts to show people what companies know about you were shut down pretty hard.
Edit: also who you vote for, what laws are passed, who goes to prison, who lives and who dies. But no they don't _directly_ give you cancer.