I think the logical fallacy you're looking for is slippery slope rather than red herring, bkev.

Do you need a special day to do that though?

Well, no, I don't really need one. But neither am I against the idea. I guess my point is this: if you don't like Valentine's Day and think that it's a vulgar over-commercialized contrivance, then you're certainly free not to celebrate it. But for those who do celebrate it, like I said before, it's as meaningful as they care to make it.

I'm not making any blanket-statement either for or against Valentine's Day. I'm just saying that choosing to participate doesn't automatically equal crass commercialization.