Winter season only.
Resort Entry tickets are highly encouraged to be pre-purchased prior to your arrival. Tickets are generally sold at the ticket box on the day, however if the resort reaches full capacity, only people will with pre-booked tickets will be allowed to enter and there won’t be any tickets sold at the ticket box.
Reaching full capacity is more likely to occur on weekends then weekdays. If you want to avoid the crowds, visit mid-week.