In O. Henry's "The Ransom of Red Chief," how do the criminals change?

When someone changes his or her thoughts or feelings in a dramatic way from the beginning of a story to the end, he or she is called a dynamic character. In O. Henry's "The Ransom of Red Chief," both of the criminals, Bill and Sam, learn a lesson that changes their minds about the benefits and lucrativeness of kidnapping. For example, at the beginning when they decide to kidnap a child to make a quick buck, the reasoning behind their thinking is as follows:

"Philoprogenitiveness, says we, is strong in semirural communities; therefore, and for other reasons, a kidnapping project ought to do better there than in the radius of newspapers that send reporters out in plain clothes to stir up talk about such things."

First of all, the word philoprogenitiveness is a noun that describes parents' strong love for their children. Thus, the criminals believe that parents in a rural community would pay any amount in order to get back a kidnapped child. These men haven't met the Dorsets, though. After a couple of days with Johnny Dorset, the criminals learn that not all parents will pay anything for the safe return of children. They also learn that kidnapping is neither beneficial to their health, nor is it lucrative. Johnny does some of the following things to change Bill and Sam's minds about kidnapping: 
When offered candy, Johnny throws a piece of a brick at Bill's eye.
He fights "like a welterweight cinnamon bear."
He likes camping out and doesn't want to go home.
He almost scalps Bill and threatens to burn Sam at the stake.
He puts a hot potato down Bill's back and stomps on it with his foot.
He throws rocks that hit Bill in the head.
He plays horsey with Bill and rides him all day long. 
Bill is the first to show signs of being a dynamic character when he tells Sam the following:

"You know, Sam . . . I've stood by you without batting an eye in earthquakes, fire, and flood--in poker games, dynamite outrages, police raids, train robberies, and cyclones. I never lost my nerve yet till we kidnapped that two-legged skyrocket of a kid."

Fortunately for them, Mr. Dorset knows that the kidnappers will discover what a handful their son is and want to return him. Ironically, and to the kidnappers' relief, Mr. Dorset offers them a way out of their own scheme. The culminating event that proves that the criminals have changed their minds about kidnapping Johnny is when they pay Mr. Dorset $250 to give the boy back rather than making any money. By paying Mr. Dorset, the criminals admit defeat and demonstrate that they have changed their minds about the benefits of the kidnapping scheme.