(Disclaimer: Myself and the people I play White Wolf games with do place fast and loose with the rules.)
A certain amount of movement happens in combat - just take a look at any fencing, boxing or MMA fight.
So the only time I’d tell a player to do that [i.e. split a die pool] in Werewolf would be if the movement was covering a large distance (like a 10m sprint) or it was complicated (like acrobatics - say back flips), and the actor doesn’t have an ability that would allow for an extra action - like spending a rage point or the Vampire ability celerity.
EDIT: World of Darkness, Core Rulebook, pg164:
”[Combat] Movement: Your character's Speed trait indicates how many yards he can travel in a single turn by walking or jogging. He can travel that many yards and still perform an action, all in the same turn. He can move and perform an action, or perform an action and then move. He cannot, however, move, perform an action and then move again all in the same turn. If he moves more quickly, he can travel up to twice his Speed trait in a turn by running. Doing so is considered a full action and no other feats can usually be performed while running. A special Merit or supernatural power is required to accomplish such combined tasks, or your character charges (see below).”
Werewolf: The Apocalypse (revised), p196
”Movement in combat: No roll is required to move, but movement takes a full action. In some situations, such as crossing treacherous ground or running amid a hail of bullets, the Storyteller may call for an Athletics roll to move or simply rule that movement at full distance is impossible.”
Hence: complicated/long distance movement and an attack (another complicated action), split your dice pool between the attack and the complex movement. Otherwise, move then attack.
And finally: WtA, p22
”…the rules in this book are useful only as a means to provide a framework for the story. If the rules conflict with the story, the story wins every time.”
If splitting a dice pool helps your game and every to have fun, do it. If it doesn’t, don’t do it and do your own thing. It’s a rule in the game.
EDIT 2: it’s worth keeping in mind garou can charge opponents, use special attacks and moves from their martial art kalindo (sp?) which can allow them to combine movement towards, or away from, an opponent and attack in one action.