You're right, it does much the same thing, but this works on external sites so a webmaster doesn't need to create a bunch of anchors to specific information on a page. Instead you can link to any site and force the browser to highlight/jump to an arbitrary location on that external site.

It's the kind of thing I'd disable because of the privacy leaks it makes possible (Ctrl-F on the new page works just as well and keeps the user in control), but I can see how some people might like the extra convenience (when it's not being used maliciously to collect sensitive information from otherwise secure websites).

It is similar, except it doesn’t require anything special in the HTML. It scrolls to an occurrence of the specified sequence of text.