[creato]

Does that setting actually matter? When I lived in the area that had these, I always forgot to set it when the number of passengers in my car changed. I never saw any difference. The charge is the same.

[OptionOfT]

Depends on the area. The 210 in Los Angeles allows you to jump on the toll-lanes for free if you have >= 3 people in the car.

And I think at certain times it's only >= 2 people.

[Retric]

It makes a difference in some locations such as I-580 5am-8pm: https://www.bayareafastrak.org/en/help/using-your-fastrak-fl...