Christmas type holiday that can be thrown into any city/town.
The addition of “irrelevant” details adds local colour to a campaign world, giving the impression that the DM has thought very deeply about the history of even the smallest architectural feature.
Elves are not actually aloof. They are actually extremely family-based and insular, and often intermarry inside their families, making them uncomfortable around those not of their family. Therefore, they shield themselves behind pretended aloofness and coldness until they are comfortable in others' company.