CAPE BRETON, Canada – Students at Greenfield Elementary and their parents learned a valuable lesson about their local teachers union and its priorities during a recent visit from Santa Claus.

Volunteer firefighters from the Scotchtown Fire Department have brought Santa to visit with kids at Greenfield Elementary for more than a half century, but that tradition came to an abrupt end this year when the visit conflicted with the NSTU “work-to-rule” protest that’s been ongoing since Dec. 5, CBC News reports.

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“We just teach,” union president Sally Capstick said of the union protest. “So that eliminates things like parties and visits from Santa, it eliminates people going in to read, it eliminates a whole lot of other things.”

Scotchtown fire chief Raymond Eksal said he was “very disappointed” when his crew showed up at the school around 9 a.m. on Monday for the annual Santa visit and was turned away after only 20 minutes.

“We don’t take sides,” he said. “We understand that they have negotiations, they have reasons for what they’re doing but it’s just a shame that the kids are the ones that have to suffer.”

Eksal said Santa and his helpers made it through about six classrooms before they were booted from the building.

“We’ve been doing that fort as long as the fire department has been running,” he told The Chronicle Herald. “It’s about building a relationship. It makes it a lot easier to talk to (the children) about fire safety.”

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“Apparently, we were somehow violating the terms of the work-to-rule,” Eksal said.

He told CBC News the situation doesn’t make any sense.

“I don’t understand it,” Eksal said. “We weren’t putting any requirements on the teachers.”

According to the Herald:

The province’s 9,300 teachers started working to rule Dec. 5 as part of their contract dispute with the government. The action means all voluntary extra-curricular activities are cancelled and teachers arrive just 20 minutes before school starts and leave 20 minutes after it ends.

In a post to Facebook, the Scotchtown Vol. Fire & Rescue wrote that Eksal “has been in contact with the relevant officials regarding today’s brief Santa visit,” and encouraged families to contact the school board with their thoughts about the episode.

The Herald attempted to contact school officials to discuss the incident but “the phone line at the school rang busy throughout the afternoon.”

Capstick, meanwhile, isn’t backing down on the Santa ban, making it clear the union puts its own interests ahead of students its members are employed to serve.

“This is unbelievably difficult when you’ve got teachers calling you up and crying because this is putting them in a situation that they don’t want to be in,” Capstick told CBC News. “But that’s the lines that were drawn.”