Mostly graphic designers prefer work on vector graphics when they work for print media. Vector graphics are easy to scalable in any dimension for any medium. Vector graphics have not fix resolution and it can be increase up to any dimension without losing its original quality.
That’s y designers always like freebies which make life easier and help them to make high-quality graphics. Designer can use all these graphics in print ads, website designs, animations etc. But before using any freebies just check the license and be sure about stated guidelines.