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.
Well, more than 50% of the total transaction volume of Bitcoin is gambling related. That's a fact we can't deny. But yes, I also agree with you that Bitcoin is more than a tool for this purpose. Will people leave that lose all their coins with gambling? Maybe, but sooner or later they will come back as Bitcoin stays in their system. They just need to make sure they stay far away from gambling.