Something that needs to happen, but isn't here - how about where you are?

I have done a fair amount of canvassing, both paid and as a volunteer in Kentucky. I've asked about this but have never gotten a satisfactory answer:

Why are we not asking for registered Dems email addresses?

One would think that the reliance upon BIG MEDIA to convey messages (either paid or unpaid) will never bring about the changes this country needs.
Email is the most cost effective way to reach huge numbers of people with information. Our state website does offer people the opportunity to sign up for email notices/newsletters, etc. which is okay but inadequate. We knock on some many people's doors, call them BUT WE STILL DON'T GET THEIR EMAIL ADDRESSES!
Does your state's Dem party do this? If so, is it successful - are people willing to give their email addresses to the state or local party when asked?