The Dog Beating Stick (the actual, physical staff) is, in physical composition, an ordinary stick of bamboo. As such, it's relatively fragile compared to metal weaponry. A strong enough martial artist can break it with his/her bare hands with minimal effort.
Even though the stick itself had no special physical properties, it had great symbolic value to the Beggar's Union. It was the symbol of the Beggar's Union Chief's personal authority within the Union and thus, whoever wielded this staff possessed great authority within wulin.
Kiu Fung never exhibited the Dog Beating Stick Technique during DGSD. When North Beggar Hung 7 Gung elected to use weaponry, he used his own personal walking stick, not the Dog Beating Stick. From Wong Yung onwards, however, the Beggar's Union Chiefs actually used the Dog Beating Stick as their personal weapon.
Was it wise to do this? As said, a bamboo stick is easily broken. It probably can't survive too many melees against powerful warriors such as West Poison Au Yeung Fung or the Golden Wheel Monk, nor can it take repeated impacts against sharp sabres and swords. On the one hand, it's just a stick...but on the other hand, that stick symbolizes the power of the Beggar's Union Chief. Risking its destruction in battle seems unwise.