Dogs have scent glands in their faces, and rubbing their faces on objects can help them to mark their territory.
Dogs groom themselves by licking and rubbing their faces. This helps to remove dirt, debris, and parasites.
Rubbing their faces can help dogs to release stress or anxiety.
Dogs may rub their faces on people or other dogs as a way of showing affection.
If a dog is not getting enough attention, they may rub their faces on people or objects as a way of trying to get attention.
When dogs are exploring their environment, they may rub their faces on things to get a better sense of their surroundings.
If you are concerned about your dog's face rubbing, it is always best to consult with a veterinarian or animal behaviorist.