George and Lennie are anomalies in the world of itinerant ranch workers. In other words, it is abnormal for two guys to travel together from town to town. The prime example of trust in this story is between George and Lennie. Their loyalty to each other trumps everything else. If and when Lennie gets into trouble, George has a backup plan to meet Lennie down the road somewhere and off they go to the next job. They stay together, regardless of the circumstances, and this is symbolic of their mutual trust. Most of these other workers travel alone and they work a job until another comes along. Near the end of Chapter 2, Slim even comments on how rare it is for two men to travel together:
Slim looked through George and beyond him. “Ain’t many guys travel around together,” he mused. “I don’t know why. Maybe ever’body in the whole damn world is scared of each other.”
Although Lennie has gotten into trouble because of his poor social skills, George stays loyal to him. And Lennie is completely loyal to George. In Chapter 3, talking with Sim again, George justifies their mutual trust as a way of avoiding the lonely life of a rancher:
"I ain’t got no people,” George said. “I seen the guys that go around on the ranches alone. That ain’t no good. They don’t have no fun. After a long time they get mean. They get wantin’ to fight all the time."
For George, their mutual trust is more than a good friendship. It is also a means of avoiding the lonely life of a wandering worker. He has seen other workers spending all of their money on prostitutes, gambling, and alcohol. In staying with Lennie and dreaming of the farm, he avoids that lonely lifestyle.