In our Class C with no slides - the enormous dinette table was more than Ed and I needed, so here's what I did:
Removed the OEM table completely. Added a floor-mounted pedestal sleeve; then made a "cafe table" out of a 2' x 2' piece of nice plywood. It really makes the "C" feel more spacious - and we like the little table so much that we put it in our 5er (which already have the floor-mounted sleeves) for our recent trip.
Our 5er normally has a table with 2 post legs - if I needed more tummy room, I'd simply make a narrower tabletop from plywood; and with 2 sleeves added to the bottom of the table, it would work in the dinette. Finish the plywood with a bit of stain and some polyurethane, and it looks nice.
I agree that some dinettes (and restaurant booths) are spaced rather closely to the table.