Here's a really good collection of references about Tanuki folklore: http://www.onmarkproductions.com/html/tanuki.shtml
Some of the things that it mentions:
Tanuki assumed human form, haunted and possessed people, and were considered omens of misfortune. Many centuries later in Japan, they evolved into irrepressible tricksters, aiming their illusory magic and mystifying belly-drum music at unwary travelers, hunters, woodsmen, and monks.
These tricksters can transform into any living or inanimate shape. Real Tanuki live in the lowlands, forests, and mountain valleys, and therefore Tanuki are most often shown playing tricks on hunters and woodsmen. But they also enjoy misleading learned scholars, and therefore shape-shift into Buddhist monks (as do foxes) with a deep knowledge of the sutras. They can cast powerful illusions (like foxes), turn pebbles and leaves into fake money or dung into a delicious-looking dinner, conjure up mirages of entire cities and palaces, appear as one-eyed demons able to produce thunder and rain, rob the bodies of the dead, and cause pebbles to rain from the sky. In some tales, they are even gifted calligraphers.
Throughout, it portrays tanuki as trickters, playing various kinds of tricks on practically everybody. So it makes sense that the title of the leader of the Tanuki Society is a "Trick master". Additionally, the article goes into some detail about the evolution of some of the lore, and less about playing tricks:
Although the Japanese continue to classify Tanuki as a yōkai 妖怪 (monster, spirit, specter, fantastic/strange being), the creature today is no longer frightening or mysterious. Instead, it has shape-changed into a harmless and amusing fellow, one more interested in encouraging generosity and cheerfulness among winers and diners than in annoying humankind with its tricks. Tanuki are also portrayed as cute and lovable characters in modern cartoons and movies -- even as mascots in commercial campaigns.
So perhaps following the evolution of the lore, the show doesn't portray them playing tricks on people all the time.