Why are you being hustled by street vendors to buy sad and drooping former roses, vegetative matter that missed the cut for bouquets, or were too late to the hospital?
Blame Esther A. Howland (1828 - 1904) of Worcester, Massachusetts. Her guilt is writ large by the Greeting Card Association's Esther Howland Award for a Greeting Card Visionary. She imported the concept to the US from Britain to bolster her father's stationery store in 1847.
Of course, it wasn't long before the stationers had infiltrated school boards and imposed the now mandatory exchange in the classroom to push the low end product of Asian children and prisoners.
Seeing the success of the card merchants, the confectioners jumped on board to fill the lull between Christmas and Easter with the benefit that the bulk of purchases would be made by desperate men with less sense of taste than a golden retriever. If the box was red, heart-shaped, and said chocolate, a man would buy it.
There were at least three Saint Valentines and all were martyrs, as they should have been for the trouble they've caused. None are the reason for the "holiday", only the excuse. They lived at a time when life and men were short and brutal, so the romantic aura of the holiday is pure piffle. At least one was reportedly part of a draft dodging scheme during the Roman Empire, marrying people so the men could avoid being deployed to foreign wars, bachelors being preferred for catapult fodder. [see Cheney, Richard]
It is to be hoped that the individual who first wrote: "Roses are red, violets are blue" was eaten by rabid wolverines, or had hemorrhoids.