It is a fact that some people will hoard lots of holiday drops for themselves, purchasing them from somebody else that has them, or beginning bogus runescape accounts and collecting them, then when the holiday drop event is over and it is not longer feasible to get them.
You should know that holiday drops are no longer tradable from now on. In the event you missed the holiday event and did not get the item, it means that you can never get it no matter what are they.
Party hats are my favorites. They come is 6 different colors, red, yellow, blue, green, white and purple. It’s one of the rare items in runescape account and presumably its value will constantly increase. Santa hat is awesome as well; it's very rare and highly priced. And it is a Christmas holiday drop in 2002. Halloween masks look beautiful, and it could have been picked up on Halloween 2002. Why not buy runescape accounts with awesome items?
Good luck! I hope this has helped you gain a small bit of insight into the world of rare items & holiday drops in runescape.