I think a great many people do that, but not everybody.
I have never been drunk in my life. I have never taken drugs. I'm 73, and I don't take any drugs - not pharmaceutical and not recreational.
This is my sister at age 62.She is now 71. Doesn't look any different.
https://www.youtube.com/watch?v=rZ4INUx49Mg
I am not American, although I lived there for 11 years. I don't watch television and don't own one. I don't listen to radio. I read extensively, so, etc.
However, that is not what is meant by voting against self-interest. What you're talking about is looking after one's health.
Yes, Americans are flooded with advertising. I've written about it many times, how it works, why people believe it.
However, when people speak about voting against their self interest, they are talking about voting for a political party, and I don't believe that to be true.
While libs are voting for 'civil rights' for minorities, conservatives are voting against having their traditional values changed.