Quote 4
[Tom Joad:] "He says it makes him feel lonesome out there in the open havin' to think what to do next. So he stole a car an' come back." (4.67)
Freedom can make you lonely. Routine drives loneliness away.
Quote 5
"We was drunk," Joad said softly. "Drunk at a dance. I don' know how she started. An' then I felt that knife go in me, an' that sobered me up. Fust thing I see is Herb comin' for me again with his knife. They was this here shovel leanin' against the school house, so I grabbed it an' smacked 'im over the head. I never had nothing against Herb. He was a nice fella." (6.92)
It's interesting that we never really learn why Herb attacks Tom in the first place.
Quote 6
[Tom Joad:] "'Course you get goddamn good an' sick a-doin' the same thing day after day for four years. If you done somepin you was ashamed of, you might think about that. But, hell, if I seen Herb Turnbull comin' for me with a knife right now, I'd squash him down with a shovel again." (6.100)
In Tom's world, there are repercussions for bad behavior, even if he likes you. Tom's all about honor.