To put in some perspective, in WOW jumping is used for:

Getting through some dungeons (BFD)
Avoiding monster attacks (Quake, etc.)
During PVP (clever use, your character keeps going forward during a jump, but you can turn around mid-jump and attack anyone behind you)
Some quests/puzzles
Several boss encounters

Poopooing jumping because some people hop around when bored seems stupid compared to the extra layer of complexity it can add to combat or other game areas.