The tide had turned by that point and most of the hard slog was behind them. They probably felt they were going to win and wanted to be part of the win. Additionally, what would they do for work? Would people look down on them as quitters or even deserters if they were not fighting for the heavily propagandized cause?
The best time to be in the army is after the heavy lifting is already done, and for some people it gives them a sense of belonging so many make a career out of it.
I've known a lot of career army people. Some love the order it imposes on their lives.
Spring and summer of 1864? They had the whole Atlanta campaign and Grants overland campaign ahead of them. Nobody was under any illusions that the war was near to being over. More hard fighting lay ahead. Yet they stayed to see it out.
Additionally, what would they do for work? Would people look down on them as quitters or even deserters if they were not fighting for the heavily propagandized cause?
But you would have us believe the war was deeply unpopular in the North. So why would the population turn against them? Public opinion certainly didn't deter Union deserters at other points of the war, and it certainly didn't deter Southern soldiers from deserting in droves.
The best time to be in the army is after the heavy lifting is already done, and for some people it gives them a sense of belonging so many make a career out of it
Your knowledge of the war truly is abysmal.