There is a significant difference bewteen something that is physically addictive and psychologically addictive. Nicotine, for example is phsyically addictive and I know this addiction very well. Currently, I have starved myself of nicotine for just over 3 months. As such, I have suffered minor withdrawal symptoms such as anxiety and irritability. This is the consequence of physical addiction.
Psychological addiction/behavioural addiction is a recurring compulsion whereby a person engages in a specific activity despite harmful consequences to the person's health, mental state, or social life. This is the kind of "addiction" (use the term very lightly) that you are talking about.
The type of behaviors that have been identified are shopping, eating, gambling, sex, internet, computers, videogames, work, exercise , spiritual obbsession, pain, cutting, shopping and pornography. Does this mean all of these behaviour are bad? No, of course not, only when people take them to extremes. Blame for this kind of addiction falls purely on the person engaging in the activity.