Robert Ziegler, president of Local 832 United Food and Commercial Workers, said the unnamed company wanted to terminate the six employees because it had found the content on the Facebook page unacceptable.
"This is a growing problem and employees have to be very, very careful of what they do," Ziegler said.
Ziegler said the popularity of such socializing websites like Facebook and MySpace is forcing individuals to take a greater degree of caution on what they print about their employers, supervisors and co-workers.
"This all falls into the category of off-duty conduct and under precedent and case law, all that can be held against you and our members can be disciplined and even fired," Ziegler said.
Ziegler said two of the employees were given a one-week suspension and four others received letters of reprimand in their personnel files.
Internet postings are the same as putting down something in writing, Ziegler said, adding employees can be held accountable for what they write, do and say.
"If an employer can prove that anything you've done affects the reputation of the company or created an atmosphere where other workers will not want to work with you, then the employer can discipline that employee," Ziegler said.
The September issue of the UFCW's monthly magazine, Union, outlines five situations in which employees can be disciplined for their actions committed away from the workplace.
The employee's conduct
* harms the company's reputation or product;
* renders him/her unable to perform his/her duties;
* leads to a refusal, reluctance or inability of other employees to work with him/her;
* constitutes a serious breach of the Criminal Code, and the reputation of the company and its employees is injured;
* places difficulty in the way of the company properly carrying out its function efficiently managing its business and efficiently direct its working forces.