It depends on the industry and also the company and whether there is some kind of compensation for workers who do their duty during holidays. Here in my country, we have a electrical power deficit, so it is normal to have people working within power generation all day and all night (different shifts) even during holidays and with relatively short vacations, because power generation is a vital part of any country which seeks to have the minimum comfort levels for their citizens.
Just think of a nuclear plant, and nuclear power generators, the nuclear core does not matter whether it is a holiday or not, it will continue to work and we need people to keep control over it, for the sake of safety and power availability..