And most importantly, they don't make you use AOL. That is by far the biggest reason not to use them.
I still remember a couple of years back where it was "the internet" provided by AOL and the real internet, where the former was a small and pathetic subset of the latter. Seeing one of my dad's employee's face when my dad typed in an actual url, and the browser actually went there, is proof of that. I have avoided association with AOL users since then whenever possible, so I don't know how this has changed, but it floored me how little people actually explored beyond the topics handed to them by AOL.