I believe God is much more generous than I and will have room for those many would care to abandon. I don't believe that is true. As long as you are giving back to the church and you are not flaunting it, there is nothing wrong with showing the world you are successful. God does not want us to live like we are in the 1800s. It's not accurate because I own one and still give more to the church every year than what I spent on my car.
Expensive cars flaunt the riches of the world and the indulgent behavior of society.
There is no excuse for a Christian to drive to church in luxury when the Outreach program doesn't have two nickels to rub together. In many cases those who are blessed with the more expensive things in life, give of their all to God and His kingdom. With all of His disciples and traveling, I think Jesus would have preferred a conversion van, or small bus. A BMW would not have been practical for His ministry. Jesus would have never done a lot of things that most Christians do today.