No need to buy more than the requirement in some games, it may be because the price of the ticket or tickets are not enough customers and interest of each game, the customer has no equal.
Customer demand for new, more demanding in some games, maybe because the price of a ticket or a ticket is not enough to attract customers and make customer requirements of each game is different.
The customer needs to buy more than sales demand in some games may be because of the price of a ticket or a ticket is not enough for the customers and the attractiveness of each game makes the customer needs are not equal.