It was a joke, but I live in the USA, and International Worker's day in May (usually the 1st, or the first monday) is not a holiday. They have their "Labord Day" that is somewhere in September
Actually May 1st is just another day for NA. Labor day is in Sept for us but unlike it seems for other countries to have the day off work on their respective Labor Day, only the kids get the day off from school. Very few places actually close to celebrate it.