If you are wondering whether or not two seater outhouses existed, they did. I saw a two seater outhouse once when we were visiting some family. Even then I wondered why two people would be sitting within inches of each other while doing their “dirty business”.
Think of the romantic moments maw and paw could share when they sat side by side, perhaps whispering in each others ear as they sat there working hard to fill up the outhouse pit. When I think about that I imagine her saying something like “I shore do love you paw but by lawd you stink worse than the hogs!”
Taking a dump in an outhouse is a little different than sitting on your shiny porcelain toilet. In an outhouse there is no flushing. Below the outhouse is a pit and when “something” drops into it, it can be loud. When the pit gets near to the top the outhouse must be moved and a new pit dug. The old pit is covered over and filled in and generally avoided by everyone. Often, later on after they all died someone else got hold of the land who didn’t know about it and wound up falling in. What will future archaeologists think about this crap?