When you get a "company car" you often get full use of the car, even for personal use, with gas covered by the company, along with maintenance. The recipient, the employee, generally only pays the taxes on the car.

The amount of taxes paid for this benefit is now under review and discussion in the Knesset Finance Committee. The main complaint is about how the amount of taxes is being determined, with no difference being made depending on the age of the car - the taxes on a 10 year old car are supposedly the same as the taxes on a new car (each on its level - not comparing a Subaru to a Mercedes, but comparing equivalent model cars).

There are other issues under discussion as well, such as the level of taxes collected on these cars, which is generally considered high. In addition, another issue, is comparing the amount of personal use and the amount of use on behalf of the company - why should the employee pay full taxes on a car that he uses mostly for work - the employer should pay or there should be some other arrangement, but it seems, the complaint goes, that the State is simply taking taxes from the people that are not being evaluated fairly.

During the discussion MK Yaakov Asher (UTJ) raised another issue to be considered. Asher wants the State to give discounts on these taxes to drivers who are Shabbos-observant. These drivers drive one day less per week and benefit from the car one day less per week so should not have to pay full taxes.
source: Ladaat

A similar model is often used by insurance companies, giving discounts on insurance for Shabbos observance, along with car rental companies. Considering the risk on the road is minimized by one day per week for such people, it makes some sort of sense to give a discount for this. Car rentals make less sense, as the car isnt available for the rental company to rent out, but they are a private commercial enterprise and for them it is a way to attract customers.

I am not sure why it might affect taxes. I choose to not use my item for one day a week, it does not help anybody else. Maybe less cars on the road? Less pollution? With insurance there is a benefit of less risk of car accidents and injury, but I am not sure why taxes should be affected, as there seems to be little benefit to the public or the State by my not using my car one day per week.

In general, taxes are too high and are a burden on the people. Any excuse to lower them, even just a bit, is good