Nurses in North Carolina accused Mission Hospital, which is owned by the for-profit hospital chain HCA Healthcare, of using the pandemic to delay a union election. At Uovo Fine Arts, a company that packages and transports art for wealthy individuals and galleries, workers said they were laid off as punishment for trying to unionize last year. Everlane, the online clothing company, laid off much of its customer-service team four days after a small number of its members informed the company’s chief executive that they had enough support to form a union. The company that owns the Cleveland newspaper The Plain Dealer this month laid off journalists who were in a guild and increased its reliance on nonunionized workers.

Companies say the layoffs are legitimate responses to an extraordinary economic crisis that has left many businesses on the cusp of collapse, not punishment for unionizing. Unionized employees tend to be more expensive, and getting rid of them can be an especially potent cost-cutting move.

Some big companies have accused workers of trying to exploit the crisis to glean public sympathy and gain momentum for unionization. A spokeswoman at Mission Hospital in Asheville, N.C., for example, said National Nurses United, the union behind the drive, “is trying to use this crisis to advance its own interest — organizing more members.”

There already have been some well-publicized cases of employees at major companies agitating for change — and then feeling that they are being punished for it.

Workers at an Amazon warehouse in Staten Island, N.Y., recently accused the company of firing employees who complained about working shoulder to shoulder in the midst of the pandemic. In a letter sent last week, the New York attorney general, Letitia James, said the company may have violated federal worker safety laws and the state’s whistle-blower protections when it fired one worker.