I tend to keep them in the cello just because quite often I'll grab a stick and take it somewhere else to smoke (bring to work to smoke on the way home etc...). Keeping it in the cello is just an extra layer of protection that helps the peace of mind. I also write the date I get the stick on the cello so I know how long they've rested and in what order to smoke in case of multiples. Though I must admit I prefer the look of a humi stocked with non cello'd sticks and have put serious thought to removing the cello.