Karva Chauth

I recently watched two SRK movies, Dilwale Dulhanie Le Jayenge and Yes Boss and in both of them the women celebrate Karva Chauth. I didn't know what it is so I looked it up.
http://en.wikipedia.org/wiki/Karva_Chauth
Married Hindu women fast on the fourth day after the full moon, in the Hindu lunisolar calendar month of Kartik, and it's supposed to bring good luck for their husbands. Unmarried women may do it for the benefit of their intended. Fasting begins at dawn and ends at moonrise. There is socializing among the women during the day and a women-only ceremony during the fast. After the moonrise
women view its reflection in a vessel filled with water, through a sieve, or through a cloth, offer the moon water for blessings and view their husbands  also indirectly. The husband breaks the woman's fast with her and may give her gifts. These days it has become commercialized and some are against it because they see it as an outdated instrument of social control directed at women. Fasting is not part of the Sikh tradition.