As someone who always relies on the race transportation, I definitely agree with this. It's too much money to pay to risk missing/being late for the race for an extra 30 minutes or sleep or whatever - ESPECIALLY when there is always at least one transportation horror story with each race (i.e. drivers not knowing where they're going*, buses not showing up on time to resorts on race morning**, etc.). Maybe I'd feel different if I were driving myself.
*Don't forget, these aren't always WDW Cast Members doing the driving - Disney has a contract with Mears to have some of their drivers come in to help with the increased load during race weekends.
**See Wilderness Lodge during Dark Side weekend (morning of the 10K I think?) for an example!