Anything that fires off the pleasure receptors in the brain can be addicting for certain people. Addiction in it's pure form is so widespread that it touches almost everything that brings people pleasure: alcohol, drugs, food, gambling, exercise, shopping, and yes, porn. I don't blame the people at Smirnoff or Heineken because I have a problem with alcohol. It's just easier to target porn specifically because it's deemed as a social taboo.