The tradition of giving gifts on this day has grown stronger every year and for some has become a fairly successful business. For example, at the beginning of the last century, it was customary for Americans to send marzipans to their brides, which were quite expensive.
In Japan, the tradition of giving sweets on this day appeared at the suggestion of one large chocolate manufacturing company. They began celebrating Valentine's Day in the 1930s, and chocolate remains the most common gift to this day. By the way, Valentine's Day there is a bit like "March 8 for men", as Japanese men receive, perhaps, even more gifts than women: men's accessories such as a razor, lotion, wallet, and so on.