I have an extremely fluid scheduled job so have experienced both and fully agree with you.

When I work Monday-Friday my weekend tends to be recovery days. I buy some cheap food to cook from a chain supermarket and I chill out at home not spending any of my hard earned cash.

When my shifts start getting a bit less traditional, (4 days on, 4 off for example) my habits change. I won't want to be stuck at home for 4 days so I'll make plans. I'll support local restaurants by eating out, and I'll make excuses to take a walk to a local coffee shop.

To put it bluntly it's just a better existence, for both me and the local economy.