What is the theme in Practical Demonkeeping: A Comedy of Horrors by Christopher Moore?

Simple pleasures is another theme in the book. When Augustus Brine decides to open his general store, it is because he wants to provide simple pleasures he associates with happiness to others. To say Brine is a follower of Zen is somewhat a misnomer, since Brine discovered Zen before he knew what it was. Brine is, instead, a natural practitioner of Zen, a person who has transcended the worries and difficulties of everyday existence. This seems to clear Brine's mind, enabling him to accept the simple pleasures of life: fishing, fine wine, fine food, sensual pleasure. These pleasures are portrayed as pure and good and the essence of good life.