where's the return coming from for the supermarket Xmas ads?

This week has seen the many of supermarket release their Christmas ads for 2017, and it's a mix of the good, the bad and the ugly.

Now these ads take a long time and a lot of money to make, so you need a pretty decent turnout at the tills just to break even, let alone get a return on your investment. So essentially, you need your existing customers to be spending more or you want new customers switching from a rival supermarket to starting spending with you.

With that in mind, let's look at the Sainsbury's ad.

On the plus side I think it's quite catchy, I quite like the realism of it and its styling ties in with their recent ad campaigns. But if I already shop with them, it doesn't give me a reason to spend more than I usually would at Christmas, and if I'm a customer of Lidl/Tesco/Morrisons etc it doesn't give me a reason to switch for my big festive shop )or any of my shop for that matter).

Which begs the question, where's the extra money coming to get that big wedge of investment back?