[JZerf]

Those lunches could add up to something significant over time. If you're paying $10 per lunch for 10 years, that's $36,500 which is pretty comparable to the cost of a car.

[Julien_r2]

Which is, then, supporting the fact that scale matter, isn't it?

Here the scale of time is larger and does make the 5$ significant, while it isn't at the scale of a few days.