It May Stop Bird Attacks or Injuries
If you park under trees often, you may have seen this happen: a bird spots its reflection in a side mirror and decides it has found a rival. It pecks. It flutters. It taps the glass again and again. Sometimes it leaves scratches, droppings, or tiny marks on the mirror housing before giving up. At times, birds even get wounded in pecking at its own reflection.
A bag can prevent that by hiding the reflective surface. The bird no longer sees another bird staring back, so there is usually nothing to challenge. This is most useful near wooded campsites, beach parking areas, quiet rural roads, or driveways where birds gather every morning.
For a solo traveler, this sounds like a small problem until it happens on a trip. You return to the car, tired and ready to leave, only to find one mirror smeared or damaged. That is the kind of tiny travel headache that feels much bigger when no one is there to help. Covering the mirror before leaving the car can reduce the chance of bird mess, mirror damage, and the annoying cleanup that follows later. It is simple, but your future self may thank you for that afterward.