As you know, urine marking is a typical behavior for a canine male. It's how he marks his territory. So most dog owners are not surprised or alarmed if their male dog lifts his leg outside to pee on a few bushes, fence posts and fire hydrants. They understand that it is normal for a dog to do this.
Some dogs have an obsession about marking their territory. After all, it is their heritage as pack members to live within a well-delineated territory. That territory contains all the commodities and valuable resources necessary to sustain the pack, including their mates and their progeny. This marking ritual makes it clear to strangers (other dogs) that they have crossed a line with respect to another pack's territory, which helps to avoid unnecessary fighting.
Here is Chester creatively marking!