Compulsion is the other side of the coin, not just negative effects. If your uncle can't give up the sauce he's an alcoholic, and if you couldn't stop reading

Compulsion is the other side of the coin, not just negative effects. If your uncle can't give up the sauce he's an alcoholic, and if you couldn't stop reading then you were absolutely addicted to books. You can be an addict (compulsive behaviour) without any negative effects at all. It's not the amount of beers you drink, it's that you can't stop.