Consider this example: https://square.github.io/crossfilter/#charts and this example https://dc-js.github.io/dc.js/#yearly-bubble-chart -- sure, you could probably do this without dc.js and crossfilter.js but it would be _a lot_ of work, and likely not re-usable.

If you don't need interactive charts that you can drill-down into, don't use it. If you do, this is the best of breed right now for this kind of thing. dc.js doesn't abstract away the d3 api -- you can still use it to your hearts content, but it sure makes these kinds of examples really easy to spin up with minimal code.