Eu acho que isso e ainda mais este link explica bem o problema.
Para este último, devo acrescentar que um machado faz uma arma muito melhor do que uma espada, tornando-a mais utilizável para o soldado de base, especialmente dada a estatura arquetípica dos anões, falta de boa destreza e qualquer disposição. para uma esplêndida luta de espadas.
Existem outras circunstâncias também. Alvo blindado? Ax / falchion / morningstar é melhor que uma espada geral. Alvo não armado? Vá buscar sua cimitarra. Não profissional / desajeitado / portador strongmente blindado? Esqueça a espada, o machado é mais fácil de usar. Fundos são limitados? Esqueça a espada, custa uma fortuna.
Nota lateral: Os anões de Tolkien manejavam espadas bem por vezes (Torin, por exemplo).
EDIT: como por solicitação, incluo a citação do segundo link no post:
Useful for chopping wood and heads alike, axes are often pressed into service as weapons. An axe's wide, cleaving head is effective against armor, making it a slower and more powerful weapon than a sword, though not quite as massive as a hammernote . Smaller axes, such as the tomahawk or the francisca, can be used as throwing weapons. In certain media, they may even return to the user's hand like a boomerang, though they have the tendency to stick in enemies if they score a hit.
Historically, due to being somewhat easier to manufacture, their general familiarity to the peasant population and mobility (real-life combat axes were small and rarely weighed more than one kilo), they used to be the close combat Weapon of Choice of the common foot soldiers, as opposed to the officers and nobility, who wore swords (which were generally too expensive for commoners). While military weapons were often illegal for peasants to own, axes are tools, and avoid the prohibition. Franks used them extensively (lending their name to the francisca), and nowadays axes are associated with dwarves, Orcs, Vikings (and other members of proud warrior races), barbarians, medieval executioners, woodcutters, firefighters, and psychopaths (giving Ax Crazy its name and meaning). If the Big Guy of a Five-Man Band isn't using a hammer or his bare fists, he'll generally use a gigantic axe as a weapon. For extra comedy, the Cute Bruiser may be given a head-chopper bigger than the rest of her body.
May also include halberds and other poleaxes, which combine the chopping power of an axe with the range of a Blade on a Stick.