The court hour is the product and it perishes. Occupancy per hour, seen in advance, is what lets you drop a price or open a slot to an open match while it can still be sold.
Four players and one payer is where cancellations start. Splitting the booking between them, each paying their share, removes the argument that ends half the reservations.
Open matches and waiting lists fill what nobody booked. Held on the same slot, a cancellation at six becomes a match at seven instead of an empty hour and the lights off.