Break away cable attachment.

I dont get it. What is the purpose?

The latest safety idea.....lol
Should be in Friday Funnies!

Maybe its stolen and that's part of the quick release should the cops start a chase...

That won't work! The safetychains will hold the van and the R clip can't be pulled out to allow the the pin to work it's way out and allow the tow tongue to drop out. All good.

Break away cable should not be connected to any part of the tow bar, in the case above, if the tow bar comes adrift from the car the cable goes with the towbar, hence no brakes will be applied.

That is about as dumb as attaching the safety chains with padlocks, yacht clips and other unrated clips that you can see on the road almost every day. There is little point having rated safety chains then attaching them to the tug with a device that is not only unrated but not even designed for that purpose. The use of padlocks as a theft deterrent is fine but please use longer chain and rated shackle/s BEFORE the padlock.
Another scary thing I have seen is the hitch pin missing altogether and the hitch secured only by the adjustable anti-rattle bolt that is fitted to the underside of some towbars to eliminate the rattle caused by the clearance between the male and female square sections.

At least the guy in the photo crossed the chains - "to be sure!"

I am reminded of (with a tiny bit of modification) >

"That is not right," said the Caterpillar.

"Not quite right, I'm afraid," said Alice, timidly:

"It is wrong from beginning to end," said the Caterpillar, decidedly; and there was silence for some minutes.

Alice in Wonderland
Ch. V, Advice from a Caterpillar
Lewis Carroll