The reason why the imperishable sect had such a rule was largely related to their cultivation method. The imperishable sect cultivated body cultivation techniques. At the beginning of cultivation, one's qi and blood would be in turmoil. Under such circumstances, one's emotions would also be very irritable. Letting them take advantage of others was also a way to vent their anger. This way, they could vent the anger in their hearts and would not develop inner demons during cultivation.
In addition to this reason, there was another reason that was related to cultivation. The human body was very magical and had great potential. After being injured, it could heal automatically. If the number of injuries increased, the body would develop a habit, and the speed of recovery would be much faster than those who were not always injured. In addition, their body cultivation techniques and some medicinal pills were more beneficial to their cultivation.