A car travels at grade, crossing numerous pedestrian paths. You need to cross streets that cars use. You do not need to cross flight paths that drones use. A dr

A car travels at grade, crossing numerous pedestrian paths. You need to cross streets that cars use. You do not need to cross flight paths that drones use. A drone can fail and land at grade, yes, but that's a major failure, whereas it only takes one misstep to walk into oncoming traffic.