Recently, while on the train, I saw a person not holding the handrails on purpose. He decided that playing a game with no outcome whatsoever was more important than his safety. In fact, he bumped into the overhead luggage carrier several times. Twice he almost stumbled and fell, with a possibly very negative outcome for him. Once he stumbled and bumped so hard into the carrier, it left a red mark on his face, even after facing it earlier. Still he refused to hold a handrail as that would have prevented him from playing the game. Clearly his addiction to the game won over any sense of self protection.
Now thinking about it, I think this is the case with most addictions. At the end, they are to some degree, harmful to the addicted person(imho). Taking this to the time when we were still facing predators, it must have been careless just to think of getting delicious berries whilst not considering the exposure to predators it came with. These individuals that are addicted (in a way) and don't care of the dangers associated with a problem, are harmed more often. Thus, making addiction an evolutionary disadvantage. Therefore, being easily addicted, as a trait, shouldn't have developed much.
Yet addiction is one of the worst problems of humanity and has been so for a long time.
So how could it develop? Are my conclusions wrong? Is addiction just a modern phenomenon? Or are there evolutionary benefits of being addicted?