A car is a depreciating asset. Are you buying these cars cash or paying out huge monthly payments in car loans?
The last thing you want to do is get stuck with a car. If you don't put enough down and it depreciates faster than you are paying it off, you might be stuck with it for a while, as your sale $$$ won't cover your loan.
It is never too early to start securing your future, and I think a lot of us wish that we started sooner. Remember with money and compounding interest it is a time game. The more you save in your 20's the better off you'll be even if you save twice as much in your 40's.
If you can afford it, I would buy some property, even a one bedroom condo, in which the payments might be equal to say paying rent and getting your own place. At your age, even entertain a two bedroom place, and have a friend move in and pay you rent. In a few yrs, the appreciation will allow you to buy a house.
If you are stll content living at home. I would go on a budget plan where you pay yourself first. Max out your 401K, put a decent chunk each month in savings, and then the rest, well, since you already saved, don't feel bad spending it on things you like.....like a car for instance. If there is enough left over, I say go for it. You already are paying yourself first, and not going broke buying these cars........and down the road you might not be able to afford these cars, so do it now while you can, but do it smart!
Hope this helps