The closer comparison one can make the better, right?

Drinking coca cola isn't illegal or even looked down upon. Rape porn isn't advertisement for rape and is not meant to encourage people to rape. Coca cola advertisement/product placements is designed to make people buy it more.

The two cases are in my opinion very different.

Do you suggest rape porn or rape scenes in movies promote more rape in the real world? What about violence in video games? I don't claim to know the answer, but I've thought that was disproved (though I haven't really looked into it).