Because trials riders can do pretty much anything. Trials riders can ride xc (probably better than most good xc riders) Trials riders can jump (well they can have a good go at it, they know the basic skills required in jumping) Trials riders can ride downhill (again they can have a good go, they know how to overcome obsticals) Trials riders can ride street, grind, spin, go fast etc. Trials riders can ride parks like bmx Trials riders can get the girls.. Well thats debateable. What I'm trying to say is that if a dirt jumper, an xc rider, a bmx rider or a downhill rider got on a trials bike and was told to "get up that wall and drop off the otherside" or similar, they wouldnt have a clue where to start. Whereas trials involves the basic skills of every type of riding. I think other riders get jellous.