We should learn to be helpful and loyal ourselves.
A truly trustworthy person must be an upright person. Such a person must never betray others for a little profit, especially not hurt his friends. Because they have their own code of conduct in mind and will strictly implement it, their moral code will never allow them to have the idea of taking advantage, no matter how they behave. People who are really greedy and cheap are often not people worthy of communication and dependence. Put yourself in others' shoes. A person who always wants to take advantage of urinating, can you trust to give them something important? Who knows what kind of choices they will make when faced with the temptation of interests? See the big from the small, don't imagine that greedy people can persist in the face of huge interest temptation.