I don't understand the point. Supermarket food is cheaper than restaurant food, virtually without exception.

But the 'routine of supermarket shopping' creates 'noise' that makes you want to eat more / more often? How does that work.

I tend to go to the supermarket once a week and make this buying decision on a full stomach. I've not bought snacks or soda during this type of shopping since I was a teenager, I simply refuse to buy these things, like cigarettes or alcohol. There is no decision fatigue, the decision was made once and stuck to.

The discipline required is about 30 minutes a week. The rest of the time I'm not at the supermarket, and travelling to the supermarket to buy a snack just isn't worth the trouble. This way sticking to the decision becomes easy: I only shop once a week.

Then I have to cook the food (I only buy ingredients). I'm not a big fan of cooking, so I wouldn't go out of my way to cook more often than I need or want, and overspend in this way.

This seems like a lot less noise or fatigue than going out for food 3 times a day and being presented with ready-made menu's of tens or even more than a hundred food options per day, and making a healthy and budget-friendly decision 21 times a week, on an empty stomach -- there's no way I could ever spend less at restaurants than cooking.

I get eating out, I've been doing it solely for the last months due to travel and I love it. But I'm absolutely not spending less or eating more healthy.