Valentine's Day is a little different in Japan:

There, the expectation is that women are to give men chocolates. According to Wikipedia, this practice "appears to have originated from the translation error of a chocolate-company executive during the initial campaigns." The Japan America Society of Greater Philadelphia explains:

Sometime in the 1950s, a Japanese chocolate manufacturer took inspiration from the western tradition of Valentine's Day and began producing heart-shaped chocolates, declaring February 14th as a day women confess their love with a gift of chocolate. The incentive was seen as an opportunity to boost the post-war economy and was a great success during a time in which Japan was eager to adopt western customs and ideas. The main difference - that only women are to bear the burden of gift-giving - is supposedly the result of a translation error made by a chocolate company executive. About a decade or so later, candy companies capitalized on the chance to balance things out urged men to give back a month later with gifts of marshmallows. This practice developed into what is now known as the March 14th holiday "White Day," on which men reciprocate with white chocolates or other small gifts to women.

I wonder how many other traditions around the world originated with misunderstandings.