Most publications require it because they're required to provide 1099s by the IRS if, cumulatively, the amount exceeds $600 in a year. It's only January, so it's quite possible it might. Most publications tend to ask the first time they pay an author, so they don't have to second guess whether it's been done. I get a new W-9 each year from publications that I haven't written for in some time. They keep it in the file for "just in case." It also keeps my mailing address up to date, which is an added benefit!