20-Year Prospect
Don't believe any of this "war on Christmas" hooey—the holiday season is as popular as it's always been. Come Black Friday, every single store in America is within Ho Ho Ho-ing distance of at least three costumed Kringles. If there's a war, Christmas is still winning it.
The only downside to Santa being so hopelessly entwined with shopping is the breakdown that happens when everyone shops online. Where does one sit on Santa's lap while shopping on Amazon or Etsy? Even Christmas photos can be done at home with a smart phone and some Photoshop skills.
Mall Santas cost money (see: Salary) and while they can also attract the crowds, it has to be worth it. Otherwise they'll just install a digital photo booth in the shape of Santa Claus that gives the children generic holiday wishes and greetings.
So, while it seems unlikely that having real live Mall Santas will go out of style in the near future, you do have to worry about the possibility that new shopping methods will close down malls altogether. Then you'll just have office parties, kids' parties, and about a million other places to showcase your Santa spirit.