My sister does that.
She just keeps the TV on at all times.
Watching a show on Netflix on her tablet? TV on.
Takes a shower and is in the bathroom for 30-45 minutes? TV on.
Leaves the house and someone is there, though not watching TV? Let's TV on. I have to shut it down myself.
I have absolutely no idea how she picked up that habit. No one in the (immediate) family does it.