Why are traditional Dutch wooden shoes curved up at the toe?

http://www.wisegeek.com/what-are-clogs.htm

Apparently is allows for a heel to ball style of walking that is easy on the foot.

Ordinary shoes and boots with either rubber or leather soles flex as you walk. True clogs with wooden soles don't. The curvature of the wooden sole is to allow comfortable walking (or dancing). 'Dutch clogs' are all wood. The ones used in Northern England are wooden sole with leather top - and believe me, they are comfortable. I've walked quite a milage in clogs. Once, they were cheap shoes for the workers. Now real clogs hard to get and rather expensive. (I'm not talking about fashion clogs here...) Practical clogs have thin rubbers under the sole to prevent excessive wear of the wooden sole - industrial ones used to be fitted with clog irons which give a lovely sound (and sparks) in dancing and walking, but they don't allow you to go into anywhere with a posh polished wood or tiled floor. https://en.wikipedia.org/wiki/Clog_%28shoe%29

Note how the form naturally appears during the production process. It would take an effort to NOT make them curved up.

http://upload.wikimedia.org/wikipedia/commons/8/83/Klompenfabricage_fasen.jpg