After the American Civil War, the dollar became very valuable. In 1899, one dollar was worth $31.22 in today's money. This is funny because beans cost 1$ in game. It also means that the robberies where you can make a million or even just 300 dollars are actually much more profitable than we normally see due to this inflation.
spoilers
When at the start of the epilogue, John only makes $3 in one day at the ranch. I thought this was poor wage originally, but when accounted for the inflation of 1907 3$ is actually worth $82.69 which is pretty good for a day's work.
Anyways I hope you enjoyed this short economics lesson.
