I've been in this situation a few times where I have something hanging out the hatch of a car. Often, there isn't really anything to hold the hatch down. But at slightly open positions like this, the handle for the hatch is perfectly oriented to clip a bungee cord on and hold it down.

Is this just a coincidence? Maybe. Still pleased me when strapping it down in the parking lot

I do wish there were actually a hook of some kind, though, for when it's significantly more open. Not that I've actually needed that.