I think sometimes couples need a justification to treat themselves and celebrate. People can get so wrapped up in their children, work, and day to day life, that they forget to appreciate their partner and relationship. Having at least one set day a year to remind them to relax and indulge each other is a great idea. That isn't to say the rest of the year they shouldn't, just sometimes people would never find the time to if there wasn't a prearranged date.