Why won’t my parents support me in getting a car?

I’m 18 years old, a student and need a car because I want to work on the side and gain practical experience. However, I would then have to pay 500-600 euros/month (leasing, insurance, fuel), so all my salary would go back to the car. An old car makes no sense (probably high workshop costs, I would have to give up my savings, less security). I asked my parents if they could at least pay for the expensive insurance (200 euros/month) and they said something like “You’re 18 and work, you can pay for your car yourself”, although we have a lot of money and a net Income of 100,000 euros per year. Then you don’t even have to do the job when everything goes back to the car. I don’t think it’s great from my parents, also because they offered my brother (15 years old) an Ellenator for 20,000 euros so that he wouldn’t get the 125 driver’s license. What do you think of the fact that my parents don’t want to support me in this regard?