I've heard that number with incentives up to 100% depending on finishing position.
But coming from someone who owned, drove, paid for my own car for 20 years, if it were me, depending on the wealth of the car owner and if we were both weekend warriors I would GLADLY drive the car for nothing, just to keep the car owner afloat. Having said that and thinking about it my guess is there isn't as many hired drivers as there used to be until you get to the upper echelon.