It was a play on words.

round - a drink of liquor apiece served at one time to each person in a group
and
the fact that dwarves are prodigiously hungry and thirsty
gives us:
They would each require their own round of cheese for a round served to the group, which is what Thorin called to be delivered to the table. Hence the price tag.

But thank you for the earnest education on delicious cheese. The pungent, well aged cheeses have always been my favorite.