This thread brings to mind a cat I used to know who lived in the 'hood. He drove a beater (an old car) and always left it unlocked. He explained to me thieves would find a way to break in, so why secure the car so it got tore up? Of course, he kept nothing of value in the car.
Me? I always got something of value in my trunk: tools, a laptop, a change of clothes, my gymbag. No way I'd leave my old beater unlocked.