I don't believe that Gambling helps Bitcoin in anyway , If someone joins the bitcoin community just for gambling then sooner or later he will lose everything and probably leave the community.
People should see Bitcoin from another perspective and not only as a gambling or a Darknet tool.
Yeah right its not only from gambling why bitcoin is growing i think bitcoins is growing because more and more site and company are accepting bitcoin .. they are boosting bitcoin because the transaction and fees are very compare to other like perfect money and paypal or other online payment processor.. and much more.