Why remove the detachable towbar

One argument for removing the towbar, however, is that many people find it annoying because it gets in the way when not in use. Second, it is necessary to remove the tow bar whenever it would obscure the vehicle’s license plate. This is not permitted on public roads.
The removable towbar in the event of an accident
In 2023, 2.5 million traffic accidents were recorded in Germany. This includes minor accidents and rear-end collisions, which often occur even at low speeds. If you haven’t removed your towbar, the towbar is also important in the event of an accident. The installed tow bar also changes the overall length of the vehicle, a factor that shouldn’t be overlooked. With a longer trailer, you’re likely to collide with another vehicle when maneuvering or parking, and even minor damage can occur.
In the event of a rear-end collision, an installed towbar can cause significant damage to the vehicle behind you. The protruding tow bar impacts the vehicle behind you with greater pressure at specific points. Depending on the angle, speed, and location of the impact, the damage to the vehicle varies. Even at low speeds, fenders are often dented or frames are distorted. In a collision without a trailer hitch, the force is distributed more evenly, so the damage is usually less.
Relevant for the insurance
So far, there are no official details or regulations from standard insurance companies regarding this either. However, since the risk of accidents and the extent of damage change with a trailer hitch that is not removed, insurance companies may assume an increased operational risk. This can lead to the vehicle owner being held jointly liable, and you may be asked to pay. There is still no official information on this.
Important to note: Replacing the towbar
If you are involved in a rear-end collision and the rear of your vehicle, including the towbar, is affected, you must absolutely replace the entire towbar. The impact from the other vehicle can damage the towbar, making it impossible to tow a trailer. Even small hairline cracks can be relevant.