From Stanton Peele on addiction:
A sensible person who is asked, “Are gambling, sex, and games addictive?” will answer, “Anything can be addictive, or not, depending on how engrossed people become in them, and how much they are damaged by it.” In other words, it isn’t which activities we focus on and call addictive, it is how the person engages in the experience (compulsively, unable to halt or to cut back, in ways that interfere with their functioning and that harm them) that counts.
Think about OCD and its diagnosis. Do we really care what people obsess or behave compulsively around? if a person endlessly organizes shoes, or washes his or her hands repeatedly, or locks and unlocks the door ad infinitum—the thing they obsess over and behave compulsively towards is not really the matter. It is the pattern of behavior they engage in and its consequences for them.
Same with addiction.