Greetings from Sweden here!
Yes, it's tradition and has been for hundreds of years. But during the 1800s or 1900s, it used to be that a group of kids would also dress up as the "Lucia tåg" translated as "Lucia line", and come to neighbour's houses or to their mother and father's room early in the morning. They'd knock on the door, the girl as Lucia holding a tray with some traditional small snacks and drinks, singing the very famous song "Santa Lucia" and other Christmas songs.
In the line; there is only one Lucia, one or more girls called "tärna" roughly translated into "bridesmaids" dressed a lot as Lucia but with tinsel in their hair instead and holding a candle, a boy or more with a big pointy hat holding a stick with a star at the end called "stärngosse" roughly translated into "star boy", and then recently during the years there's been added a santa or more at the rear of the line. Sometimes there can be a "pepparkaksgubbe/gumma" or more translated as "gingerbread men/ladies", but that's very new and only for the little kids mostly. And for more adult Santa Lucia lines, nor the gingerbreadman or the Santa are there.
Every year on the 13th of December here in Sweden, all the students in schools and such go to a church, or a big hallway or some sort of an assembly, where you get to see other children or teenagers walk in in this line and then stand and sing for the audience. All over the country there are also groups of young adults singing, that are recorded and then sent on the television for those at home.
A brief fun fact about Santa Lucia here in Sweden. However I do not know how it looks like in Italy.
Love the art, by the way.