This isn't really a solution when you start multiplying the # of carriers (USPS/UPS/FedEx/Ontrac/etc) that deliver in the US, to the number of packages that heavy e-commerce users receive per month. It's not unusual for people with Amazon Prime accounts to have 10+ packages delivered in a month. If they would have to go to different locations to pick up all these packages, then it quickly negates much of the convenience/experience of shopping online.