I think the concern should be laid at the feet of people with an addictive personality, not the game. Anything can be addictive. Sure, games, ice cream, pizza, drugs, and sex are all well known for being 'addictive'.
But people could be addictive to drying clothes, wearing ladies underwear, eating paper... strange stuff. That's on the person, not the product.
Aside from causing intense pain, the venom of the spider can also cause priapism in humans. Erections resulting from the bite are uncomfortable, can last for many hours and can lead to impotence. A component of the venom (Tx2-6) is being studied for use in erectile dysfunction treatments.