It is because the state & the workers have not decided what to do for the holiday payment.
Why could not the State put it in the contract, for if it employs people for the museum, it knows from the start that they should work on Sundays? I know that my argument is over-simplistic, but all these inefficacy and nonchalance is painfully annoying.
Today all the shops are closed because it is holiday. While in Italy the opening timetable is fully liberalized to stimulate the economy and employment, here in Greece there is not even such a discussion.
How it is possible?