Unfortunately, too many people have a problem with littering and treating areas like their own personal trash can. In an ideal world, trash would not be such a huge problem. But there should be enough people to help clean up trash. In my neighborhood, after any big event there are many volunteers helping to clean up afterwards.
People pay high prices to attend such events as the 500 and they should not be expected to pick up after the litter bugs. In a perfect world, everyone would pick up after themselves and there would be no need for a mass cleanup after an event. But with the high prices people pay to attend, the event organizers should pay a cleaning crew-not expect event-goers to spend their time cleaning afterward.
Volunteers are not needed. What is needed is common sense and manners by those attending the event. If each person picked up their own trash, there would not be such a huge mess. It almost seems as if they feel self-entitled to leave a mess because "someone else will pick it up".
People should not volunteer to clean the trash after events, especially when they have paid an extremely large amount of money to attend the event. Consider trash cleanup and removal to be built into the cost of attending the event and incorporated into the ticket price. To encourage better cleanup, perhaps the ticket should line item the cost associated with cleanup to encourage people to throw it away.