Setting is the United States sometime in the near future, but information about Central and South American practices would also be useful.
If a person has a surname such as "de la Garza", would he ever be referred to simply as Garza? Or would a news account about him always refer to him as de la Garza? I know that such prepositions are dropped in German (Maria von Trapp's book was The Story of the Trapp Family Singers, for example) but I have no idea how this would be treated in Spanish.
This question was sparked by an old Zorro movie in which Diego de la Vega and his father were sometimes referred to as Vega but never (that I noticed) as de la Vega. I realize that Hollywood lies, and vintage Hollywood lies even more, but on the off-chance that that was actually accurate and not an antiquated practice, I figured I'd ask, as I have a couple characters with surnames like this.