I can understand why in some situations we might need a "hard copy" of a document. But in my line of work, I see people print a lot of things that don't need to be printed. I generally tend to print things to a PDF file and then read them on my laptop or tablet. Where I see the biggest part of the problem is when business have to print documents that require "original signatures" to make them valid. I consider this to be a failure of the encryption and authentication methods used today by IT.
If we had a secure and easy to use method of identifying ourselves via a cryptographic token, and the method was legally accepted by the US Government and business, I'm sure the pile of paper I had to deal with the last time I bought a house would be reduced drastically. We do have methods for signing a PDF file with a cryptographic token, but I don't think the legal system has caught up with it yet. Also the technology is not as wide-spread as it should be.