> The parking spaces for cars are specifically marked by the city.

Is that true in the US?

In Ireland, by default you're allowed park on the side of the road. There are exceptions, ie you can't cause an obstruction to traffic, block an entrance, park where road markings prohibit it, or within certain distances of a junction. However, if none of the above apply, you don't need to find a marked parking space - you can just park.