When the first department store Santa appeared in 1890, it wasn’t just a cross section of Christmas and commerce. It was also a major step in the evolution of Santa Claus.
(The Santa at Montreal department store Eaton’s in 1946.)
In the 20th century it became common during December in large shops or department stores to have a "cavern" in which an actor dressed up as Santa Claus would give gifts to children. Grottos can be large walk-through fantasy cavern-like areas incorporating animatronic characters such as elves and pantomime characters. This tradition started in Britain in 1879 and then extended in the 1890s to Australian and American department stores seeking to attract customers.  It is traditional that the children receive a toy from Father Christmas upon visiting Santa.
As Christmas approaches, children around the world have Santa on the brain. Anxiously waiting to meet the jolly guy, wondering if they've been overly naughty or sufficiently nice, and eagerly daydreaming about their potential gift hauls whispered in Santa's ear upon their annual visit to Santa's castle.