answer:It’s already starting. Micro-Center, Chilis Restaurant, Home Depot, and my local public library already send me email receipts when I purchase something (or in the case of the library, check out books). There will always need to be an option to get a paper receipt, for tax and/or return purposes. To say nothing of proof of purchase so you aren’t accused of shoplifting. But I think that the leading edge companies and services are already doing this on a small scale. [Pharmacies have different obligations. Receipts have to show tax deductibility and whether something is medicine or not. The pharmacy also has to give you medicine information and instructions. I’m not sure that will ever change.]