That's only part of the story. Contrary to popular opinion, St. Nicholas isn't the sole basis for Santa Claus mythology.
Santa is a combination of St. Nick, Norse and Germanic gods, and other Christmas figures such as Father Christmas/Pere Noel. I suggest you educate yourself in those facts before simply copying and pasting what someone else thinks it is.
So if Santa is already a combination of a bunch of different bits of lore and legend, I have absolutely no problem with anyone ascribing to Santa qualities outside what we in the 21st century feel is tradition. To deny someone that ability is nothing short of hypocrisy, considering someone 1000 years ago would likely be confused or angry over what "our" definition of Santa (reindeer, elves) has become.
Simply put, since "your" Santa is already a bastard, you don't get to complain about the bastardization of "their" Santa.