People think RuneScape is fun. I actually though it was fun myself too. I played for about 1 year or two with a few friends from school. We all liked it, enjoyed it and finally quit it.
RuneScape was an addicting game I agree, some people loved it as soon as they entered the Tutorial Island of RuneScape, and some left because they didn't know how to burn fish… Buy why did some leave and others stay? I have done some research, and this is what I think about the people that play and stay on the game.
Players that purely enjoyed the game because of one simple aspect many MMORPG's don't have: downloading. OK, you do have to download the few MB from the games system's and engines, but, it's so small, you can't really classify it as a download. I haven't played RuneScape for about 4 - 5 years, yet, it still only took about 5 - 10 short minutes to download the entire game. Bravo Jagex for Java based MMORPG!
Addicts may have also stayed to enjoy the game because of the simple game play. It is easy to learn how to play (I don't know why some people cannot complete a detailed course in the Tutorial Island) and challenging. It challenge you simply by pushing you to either finish the difficult quest, get 99 in a skill or too get the Blue Party hat. Questing may seem simple too a lot of people but getting 99 in a skill or getting a rare is quite something to cheer about. This is because getting 99 in a skill will takes weeks or months, depending on how much you pay, getting a skill to 80 is probably stressful enough. Even with the mini game: Pest Control, it will take many weeks to accumulate enough tickets to gain the enough experience needed for the big 99.
Accumulating a rare is possibly even harder now, it is almost impossible to merchant or to lure someone with one. With the new 3,000 GP trade rule, it is almost impossible to make even 2,000,000 GP a day which used to take only a few hours before this rule.
Some people may have purely played this game because of peer pressure. I know schools that literally have "clubs" on this game. They talk about RuneScape, they draw about RuneScape, they write about RuneScape, they're assignments are POSSIBLY about RuneScape… It's madness! If one person seems to be left out because they don't play this Java based MMORPG, they will probably more than definitely want to join in and play the game themselves.
Gamers may also consider this game because of the member facility. It provides you with Mini-Games and a couple of member only skills which can be quite fun to train. Member features such as Castle Wars or Barbarian Assault, mini games I loved to play when I was a member. They were challenging and tactful.