Regardless if you playing for fun, or playing for the profits, if you play beyond the normal level you are expected to play, and you get so involved, you can become addicted, same ways if you win or you lose in gambling you can still be addicted.
What matters is how you gambling, and not or what you get from gambling, whatever you do too much is already addictions, when it becomes uncontrollably done multiple times
You are absolutely correct that is the real truth about it because even gamblers that often gamble for fun and entertainment can also get addicted if they don't have a self control.
So however, in which ever way you are approaching gambling the most important thing is noing when to stop and call it a day without thinking of going above your limit that is why most gamblers normally have problem.