Most imaging for offset printing is done in PostScript, which can render EPS directly, so there's no format conversion. For web publishing that's not the case, and either is probably fine depending on the workflow.
Reason is quite simple. EPS is based on PostScript. PDF specification contains a subset of PostScript. Embedding EPS into PDF is trivial and yields high quality results. For a printing publication workflow having EPS files at hand saves a lot of time and problems.
SVG is nice too, just needs few more intermediate steps.
