There are an untold number of stories on the internet where teenagers have absent parents. While this can give the writer of the story more leeway into what their young characters can do, it is also very unrealistic.
This is not to say that there are no parents out there who leave their children alone for long periods of time. Nor am I saying that there are no parents who care as little for their children as they do for a stranger. What I am saying is that these scenarios are not the norm and constitute bad parenting.
If parents leave their under-aged children alone, there must be a reason. For instance, the parent may work away from home or during the evenings. Single parents may need to work several jobs. Other parents may be neglectful because they never wanted kids or they want to party.
Regardless of the reason for the under-aged children being left alone, there are consequences.