Why discontinued rs items and holiday drops runescape gold expensive? This is due to the reason that these items are not available for distribution anymore as these are only events or seasonal items. These items can be get from events or seasons where in they are being release on certain dates. Though they are not available to be acquire from drops or NPC, they are still able to use and be traded from other players.

More information of the rarity of these items and make runescape gold from it

There are players who are just storing rares for them to make runescape gold from it. They store it since there will be no point of selling it when it’s in season. The reason for this is that when an item is in season every player in runescape will also have the same rare rs items. While having a huge number of rares in your rs account might lead you to get banned. Placing the discontinued or holiday drops after several months in the playerauctions grand exchange is advisable.