"But Hostess kept asking for concessions in exchange to keep the plants open, and either workers gave away all their power to control wages or the plants closed," Opler said. "It was a no-win situation. I'm not sure this was a case of the union overplaying its hand or not having a hand to play."
For Christopher Rhomberg, a Fordham University sociology professor, the strike went beyond wages and benefits.
"The workers had good reason to doubt management's intentions and reorganization plan," Rhomberg said. "The company had gone through bankruptcy twice in the last eight years and a revolving door of management teams that increased the firm's debt but failed to reinvest in production or new products."
Only 14.3 million of all U.S. workers belong to unions, according to the Bureau of Labor Statistics—just 11.3 percent of the total workforce. That's the lowest rate in 70 years. The peak for union workers was a 35 percent rate during the mid-1950s, after a surge in unionization during the Great Depression through post-World War II.
Most union workers are public sector employees, and only 7 percent are private sector workers—like those from Hostess—belonging to unions, according to the BLS.
The low membership reflect how irrelevant unions have become, said John Alan James, a business management consultant and staff member at Pace University.
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"Unions have been very good in the past making sure we have benefits like maternity leave, but their leadership continues to think only of themselves and not their members," James said.
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"Employees are left to ask themselves why should I pay dues when I don't see any positive results," he added.
"The business world is too fast today, and businesses need to make fast decisions and can't wait for unions to make up their minds," Bloch said. "Unions have to convince their membership that a deal is good or not, and that takes too much time these days."
If it does take time, some workers seem wiling to wait. Job actions and walkouts by fast-food workers in the last few months at McDonald's, Subway and Dunkin' Donuts in Chicago and New York have called for higher wages and the right to form a union without interference. Workers at retailers Sears, Macy's and Victoria's Secret have done the same.
Fast-food and retail workers bring more than $4 billion a year into Chicago cash registers. But most of them earn Illinois' minimum hourly wage of $8.25, or just above it. They say they are forced to rely on public assistance to provide for their families and get health care for their children. They're asking for $15 an hour and the right to form a union to support their families and put money back into the economy.
But even workers' taking to the streets doesn't mean things will get better for labor, Opler said.
"I've argued that unless things change dramatically, the labor movement is in serious trouble of becoming obsolete," he said. "Unions have lost their power to prevent lower wages and the increase in working hours."
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"But I would likely have been making that claim in 1929 and 1930 as the labor movement was one the eve of a historical period of growth," Opler said.
As for Hostess, it will start hiring this weekend at the Dolly Madison Bakery in Columbus, Ga., one of the locations shut down when the old company closed.
Hostess executive vice president Michael Cramer told NBC on Thursday, "We are not going to invite the unions in. We don't have to." Cramer did add that nothing prevents workers from unionizing at some point.
Bloch said Hostess might want to keep even a hint of unionionization out of the workforce, but it can't.
"They would be inviting trouble, if they tried to screen potential workers about their feeling on unions," the labor lawyer said.
"There are employee laws to protect anyone from discrimination about unions. They can't ask if someone is pro-union or not," Bloch said. "Who knows? Unions could end up back in Hostess and the whole thing might happen again."