Is it not rude to separate couples?

When arranging seating for a dinner (not that often), we tend to separate couples. And when at someone's house when there is not pre-arranged seating, my wife and I tend to sit apart.

Stendhal thought that the 19th Century French custom that married couples should attend the same gatherings had harmed the quality of conversation. I think he said this of the Empire.

probably depends, but couples already have all the other times they can be with each other