I don't think my parents dislike Runescape at all, they think it is a pretty cool game and they tease me and my little brothers for playing it.
I DO think that my parents secretly think Runescape is just a waste of time that we could be using to do homework, chores, or any sort of productive activity that is instead spent sitting in front of a computer for hours at a time. They let us play and aren't too vocal about it if they don't like it, but I have heard them make snide comments about RS more than once.
I am sure that from a parent's perspective, they would care far less about the game if it was something that I only played a little bit in my spare time, but unfortunately I spend many hours a day on RS and/or Sythe doing RS related things, and in the end it is just a giant waste of my time. But they are not objective to it aslong as other important things are getting done, and I'm sure they would much rather have me at home playing RS than out on the streets getting in to trouble like I was prior to this past June when I moved back in with them.