vacation days are there for people to use if they need them ... some people move first in the 'easier' games (like ludo), and then in games which require more thinking (like chess) .. so you will see more people use vacation days for games like chess than they will use them for games like ludo

the problem with vacation days is that someone can use them all up before the end of the year .. and then simply renew his/her membership to get a new stock .. for some people the price of a membership isnt a problem to pay several times a year and so they can have a LOT of vacation days