Thats true, because as you complete quests you unlock more items for other quests, but since only 2 'random' items appear per level & you are unlocking more items it reduces your chances of getting an item you need for a quest (or for points or powers). So collecting items earlier on, like candles, is easier because there were fewer items you had access to at the time. There are a handful of items that wont appear again after the quest they are for is complete (like the snowflake). Also it depends on how often you play & how many levels you get through on average in a game that affect how long it takes.
I'm stuck on 9 bulbs at the moment, and get 3 free games a week and have been collecting bulbs for about 2 months. So close.
Sorry about the length.
