The least way sidewalks are used in Cambodia is for walking. When they aren’t being used for parking lots, they become the showroom for the business at that address.
One thought that always occurs to me when I go past these business establishments is the time required for setting up and taking down of everything on the sidewalk, day after day. Then I think–the proprietors don’t have anything else to do. Using 45 minutes or an hour to move everything out of the shop on to the sidewalk and then moving it back inside at the end of the day may be the high point of the day, when something actually happens. Otherwise they just sit and wait for custom.