Every organization have their policy that they guide jealously and depending on the nature of the job, the employment letters are drafted and in the contract, the company will state it clearly what free time or off days are available for the employee and both parties signs. There is something called leave which the employee is entitled to and as soon as that is exhausted, he is bound to appear at work irrespective of what season it is. Some organization go as far as paying enticing overtime bonuses to their staffs that will work during the holidays while others recruit ad hoc staffs to cover for jobs during the holidays should large number of their workforce decide to go for leave during the holiday seasons. No employee will be forced to work during holidays instead they are enticed with good offers because forcing someone to work is against the law and no organization would want to go against the law.