I think you have your facts a little sideways -- most millionaires get that way by not spending money.
There are a lot of millionaires in the country, but most of them (like me) would not impress you...mostly because they aren't that rich -- relatively speaking -- and they do not spend money.
The average millionaire is a retiree or a business owner (sometimes both). They have a lot of money mainly because they didn't spend it and invested well.
The math works this way: $1 million in assets equals about $50,000 a year for 30 years. Keeping in mind that $45,000 a year is considered "a typical family income in the US."
In general, you need $5-$10 million to easily spend "a lot" every year and stay rich for a long time. If you are going to retire at 40, you will need to stay rich for a long time...40 years or more.
To start thinking about dozens of cars and yachts and spending what ever you want, whenever you want to and never running out of money -- you need to be super rich: $25 million or more in assets. This is very, very rare.