Originally Posted by DirtyProfits

For companies it's popular because they must not spend their money on cars all at once but can take it for other investments and just pay a monthly fee for their cars.
Imagine a company has 100 employees and everybody gets a company car that'd be 100 x $30k = $3 million or they lease 100 cars and only pay 100 x $300 per month. So they can take the other ~ $2 million and maximize the money.