I first played Bubble Bobble as the Commodore 64 version, around 1989. Once we learned the simple rules, my twin sister and I were addicted to the gameplay. The Commodore 64 graphics were of a much lower quality than the arcade version, so it wasn't until I discovered MAME (around 2000) that I realized how "cute" the original arcade graphics were. It's a good thing I didn't know that then, or else it might have turned me off of the game.
At our young age, Bubble Bobble was a rare activity that my sister and I could enjoy together without squabbles or arguments. Our goal was to see how far we could get. Although, back then we only ever got to about round 13 -- the heart level -- and I think that was using the warp umbrella. After practicing on MAME we could get much farther. (The Insert Coin key helps a lot too.) We once got to the level with the "forever falling" mid sections and the "holding wells" on the sides. We hadn't quite mastered the bubble hopping to get all the way out of the holding wells in an easy, repeatable way and so we eventually gave up instead of putting another quarter in.
I found a website that details all the items in Bubble Bobble, what they do, and when they are awarded. Some of the items make more sense after reading it. For example, I always wondered why the umbrella was used as a level warp item. It turns out you are awarded an umbrella for popping lots of water bubbles. After reading all the rules, Bubble Bobble seemed like an intricate slot machine to me. The list of the food items and their point values reminded me of a slot machine's payoff table, especially the fruits. And the mechanistic, repeatable, never-ending gameplay has the same addictive appeal as a slot machine: preform the steps, win the prize, and go on to the next round.
When I read about the secret levels and various endings, I succumbed to temptation and used the cheat features of MAME to see what they looked like. To my surprise, I recognized the ending music from the arcade version was the same as the title music for the Commodore 64 version. It's a shame that when a band covers the Bubble Bobble music they only do the in-game tune. Although it's instantly recognizable to anyone who's played the game, it's too short and repetitive to be musically interesting. The end-game tune is more catchy; however, I guess it's also a little too cheesy to actually cover.
Bubble Bobble Info Pages
Explanations of all the items and rules of Bubble Bobble.