There are some people who play Santa Claus that earn a lot of money; Hollywood actors like Kurt Russell and Ed Asner come to mind. Of course, these are "real" actors, not Santas, but the line does get blurry. I and many members of The Santa Claus Conservatory have appeared in commercials, TV shows, and movies. These things can add substantially to a Santa's income.
Same with being a "brand ambassador." Many Santas, including me, have partnered with brands to be their ambassador of the Christmas spirit.
Many Santas spend time in October and early November working the photo studios — this too can increase a Santa's income.
So the question of income is difficult to answer, ranging typically to a few thousand dollars for a mall or retail Santa to $30,000 — $40,0000 or even $50,000 or more (sometimes much more) for the very few Santas who work year round and pursue work in the entertainment industry, or become brand ambassadors.