Of course it is.  Twyla DeVito, a bartender at a Shelby, OH, American Legion establishment, was fired for calling the police about a drunken patron who was leaving the bar in his vehicle.  She had this:

“I came into work, he was already there, pretty much hammered. … He ordered a beer, I gave it to him, and then I started to try to slow it down, serving him.”
She said that when he went to leave, she knew he was not in a state to drive.
“I called the police and said, ‘We have a very drunk person leaving the bar. He is going to kill someone or himself,'” [she said.]

The police caught up with him, and his breathalyzer test came out 0.167—twice the legal limit.  After that, Mic Hummard, her boss, fired her, saying

…it’s bad for business to have a bartender that will call the cops.  If every patron who comes in here has to worry about the cops waiting for them when they leave, the place would be empty.

Amazingly, he added that while DeVito did the right thing morally, she did not do the right thing for the business.