You must look at this from a risk/reward perspective. Each type of record you mention above (any many other routine communications) affect your relationship with a customer. Regardless of the type of information you are communicating to a customer, stop and think about the possible consequences of customer repudiation ("I didn't receive it", "it wasn't legible", "it didn't mention...", "...and I don't care what you say now, it has no effect on me.")
A good risk manager will consider the possibility of unfortunate outcomes and invest most heavily in measures dealing with the most serious. Here, the investment is the time and trouble of setting up and management of the mechanism necessary to obtain bullet-proof "informed, demonstrable consent." Payback comes from any savings that result from conversion of paper to electrons.
If paper got the job done and the cost per customer was modest, do you really want to open a new avenue for customer complaints and possible repudiation?