The wheels of a car really need to be perfectly aligned. If the left wheel is facing exactly straight, then the right wheel should NOT be 0.5 degrees turned in either direction. But various bumps on the road and general stress may cause little errors like this to develop. Other variations exist where the wheels become just a little bit "off" from perfectly aligned.

This causes increased wear and tear, especially on the tires, and reduced mileage.

Getting that checked and corrected can be done as part of regular vehicle maintenance.