A rack for my bike has always been the 1st or 2nd purchase after the bike itself. The rack came first until the late '70s, when helmets that looked like they offered real protection cam on the market. Like others, I don't understand why you don't think racks work on non-motorized bikes.
I can't see myself riding an e-bike, either, but if I needed a tool to help me earn money delivering things, an e-bike would be high on my list of want-to-buys.