I’ve seen some flowing like these, usually involving people who were quite high, or very drunk, or in a table with a bunch of psychology students, I wouldn’t say any of these cases are “natural.” But a weird might be enough to drag others into weird arguments, like during that mixer where conversation was basically normal until Shinonome opened her mouth.
Also, sample bias to make the narrative concise, they might be having some trivial idle talk when they meet on campus but this just not shown to the readers and we’re just seeing the important ones.