Why are Jim and Dave arguing in the store in Chapter 6 of Their Eyes Were Watching God?
Jim and Dave are arguing over which of them is more in love with Daisy. The boys are "act(ing) out their rivalry", and although their argument is for the most part light-hearted, "everybody (knows) they (mean) some of it" too.
Daisy is an attractive woman;
"she is black and she knows that white clothes look good on her, so she wears them for dress up...she's got those big black eyes with pleny shiny white in them that makes them shine like brand new money and she knows what God gave women eyelashes for, too".
When Daisy arrives, Jim and Dave, who are hanging out on the porch, begin a repartee, with each declaring that his love for her is greater than the other's. Dave starts the contest by asking Jim how much time he is willing to make for Daisy, to which Jim quickly responds "twenty yeahs!" Dave makes a joke out of his rival's offer, illustrating humorously that he himself "wouldn't take nothin' less than life". Jim, then, takes a turn at demanding a test. He challenges Dave to declare what he would do for Daisy "if she was to turn fool enough tuh marry (him)". Dave says he would buy Daisy a passenger train, but Jim one-ups him by saying that he, in turn would get her a steamship, with some men to run it for her. Dave offers to top that, telling Daisy that he would "take uh job cleanin' out de Atlantic Ocean...anytime (she) say(s) (she) so desires", to which Jim counters by saying that he would step off "uh earoplane way up in de sky", just to walk her home.
The crowd gathered on the porch and in the store get a kick out of Jim and Dave's "argument", laughing raucously as each man tries to outdo the other. They know "it's not courtship...it's acting-out courship and everybody is in the play" (Chapter 6).