I believe they want it to be seen in theaters and not on Netflix, etc. so that it won't die a quick death They want/need hooplah and critics reviews and awards - that will bring attention to it. People have to be talking about it so that they will be curious to see it and ideally, eventually public perception shifts. That won't happen on Netflix.
I was lucky enough to see it when I attended the VTA conference in DC in early June (I attended the VTA conf. as an enthusiastic consumer, not as a vendor). As a vaper it's comforting to know the truth is being told but it's definitely not made for vapers - the people that need to see it are the people who look at you sideways when you're walking down the street vaping, your brother in law who is spouting out propaganda and mis-information from "legitimate" health organizations, your co-worker who walks by you and says "Those are worse than cigarettes!!" and refuses to listen to anything you have to say, and on and on. People who don't vape need to see this. There will not be enough of them that "happen to" decide to watch it on Netflix where it would make an impact on public perception/awareness.