Pets right on public road

I have two Labradors that I take for walks three times a day. In my colony, there is a row of houses, followed by an open strip of land, then a road, and beyond that another large open public space next to a drainage channel. I make a conscious effort not to let my dogs pee near people's houses, the space directly outside their homes, or on the road. Instead, I walk them in the open area next to the drainage channel. People also park their vehicles in this public space. Occasionally, one of my dogs ends up peeing on a parked vehicle. This isn't something I deliberately encourage or can fully control. A neighbour has asked me not to let my dog pee there, but since the vehicles are parked in a public space, I'm unsure what the expectation is. My dog is also likely reacting to scent-marking, as many street dogs pee in the same area, which naturally encourages other dogs to mark their territory. So my question is: if a vehicle is parked in a public open space, is a dog not allowed to pee there? I understand it can be unpleasant, but I don't intentionally make my dog pee on anyone's vehicle.