I just sit on the floor and have the machine on the floor in front of me, but I am pretty flexible:).
I have used a campsite picnic table as a cutting table, and I could see running an extension cord and sewing out there, for a larger project, or putting the machine on a sturdy folding table that I bring sometimes for cooking.
Things have to have multiple uses when camping, right?
If your dining table is too high in relation to the seat, you could try putting a cushion under you and a book or block of wood under the pedal. Might work :)