“I cannot come to you,” Katie Williams was told, seconds after her Grab driver had accepted her request for a ride in Canggu. “I cannot come to you. You need to come meet me.”Williams, an Australian tourist in her mid-thirties, explained through the app that her elderly parents struggled to walk very far in the hot Bali sun. The driver’s reply was blunt: “It’s too dangerous. I cannot come.”After two more cancellations, she eventually relented and paid a local driver twice the original...