That's an excellent question about a detail many of us see every day but might not think much about! In most cities, you'll actually find a mix of both wheeled and stationary trash cans, each serving a specific purpose.
Stationary trash cans are the most common type you see permanently bolted or cemented to the ground in public spaces like parks, on street corners, and near benches. Their main job is to provide a fixed, reliable spot for pedestrians to dispose of small litter like wrappers or coffee cups. Because they are anchored, they are less likely to be stolen or knocked over by wind or vandals.
On the other hand, wheeled trash cans are the true workhorses of city sanitation. You'll often spot these larger, heavy-duty bins behind restaurants, in apartment complex alleys, or at commercial locations. The wheels are absolutely essential for the sanitation workers who need to quickly and safely roll these heavy, full bins to the garbage truck for emptying. This design significantly reduces the risk of injury from lifting.
So, to sum it up: stationary bins are for convenient public litter disposal, while wheeled bins are for high-volume, commercial waste that needs to be moved efficiently. The choice depends entirely on the location and the specific waste management needs of that area. It's a simple but clever system that helps keep our urban environments clean!