You may be missing the "wet/dry trickle filter box" in the sump only generally.
But wet/drys have a sump, and plain sump, eg no wet/dry is just a plain sump, generally they use a sock filter and some sponge/biomedia.

In marine tanks, the sump is the typical set up, using a refugium perhaps, or a large skimmer and maybe some live rock, and the sock filter.

I'll likely convert most of my tanks to sumps once I move.


Regards,
Tom Barr