[chryuop]

Every object, person or animal in Japanese have to have a counter in order to express a quantity. 枚 is used to count flat objects. So if you want to count the tickets, you can't simply say ニチケット, but you need to place a counter. For tickets the counter is 枚, so becomes 二枚のチケット. There are different counters, so for example if you want to say 2 dogs it will be ニ匹の犬 since the counter used for small pets is 匹 (ひき).