The Pursuit of Effective Email Capture

I read the following article which got me thinking about the most effective way for businesses to capture customer emails.

http://adage.com/article/digitalnext/marketers-lost-email-capture-war-3-ways-turn-tide/307927/

The premise of the article is that the most common way of collecting a customer's email (enrollment upon checkout) is not a very effective way because the transaction is already complete and we are all increasingly wary of adding another daily email to our inbox just for occasional sales in the future. The article focuses on three strategic ways to capture email that offer more to the consumer:

1) Enter email for free wifi in store. While this may be a good idea in concept, it doesn't seem to be the best area to focus on as we are moving towards a world of unlimited data packages and ubiquitous wifi. It also requires the customer to be focused on his/her phone, enter email etc. Given the cost to the retailer to maintain wifi, this does not seem to be the best option to me

2) Digital Receipts. Again, in concept this seems like a smart idea and I agree that we will eventually move away from paper receipts. However, typing in an email on a small touch screen at POS is still not efficient enough for me to use it. I can see this being the norm as soon as the technology advances enough where people do not have to type in an email at a time when they are frequently just trying to leave the store as soon as possible. In my opinion, this will become very valuable to retailers as soon as it can synced with some form of voice control/scanning/auto-population.

3) Technological Innovations. It was reported today that Warrett Buffett sold off $900m worth of Walmart stock in the last quarter, primarily because of their belief in the future of brick and mortar and Walmart's failure to advance its e-commerce. In my opinion, this pretty much sums it up for the future of conventional brick and mortar retail. Brick and mortar will need to advance its technology to find a middle ground between e-commerce and the in-store experience. An example given is how Crate and Barrel offers its shoppers tablets, with which they can scan items and receive more info (once they enter their email). Although this approach requires a much larger investment on behalf of the retailer, this is where I would focus my efforts (in order to get emails as well as grow sales).