create "Beach booking" online service
Create online service to book spot on the beach (for example 10' x 10'). System will record the reservation, generate parking ticket and take garbage deposit. At the end if place was left tidy - return deposit and rate the customer. Customers with the higher rate will receive discounts for future reservations.
Actually, Wasaga Beach is going to implement similar approach - they will have limited number of people in dedicated zones and put hand stamps for re-entry
This is only good if it applies to everyone including locals
Blake Cousins commented
Rewarding good behaviour seems like an incentive that might work, especially with payment systems being able to easily accommodate something like this.