Hmmmm…I don’t remember being surveyed on that, but maybe they weren’t asking us seniors :). Either way, the excuse teachers used to give us was that, shockingly, the student body voted to keep them back in the mid 2010s, so it’s interesting to see how that sentiment has changed (although I am not surprised).
I was a day student at Lawrenceville, and I can definitely attest to this. My parents are certainly very relieved about not having to wake up on Saturday mornings, but other than that, Saturday classes were a huge boon for me—even though we have a much larger day student population than our peer schools, I would certainly say that our day students were very well integrated into the student population at large (to the extent that the school president my junior year was one). It gave me an excuse to go to campus on Saturdays, and from there I was able to stay into the night/until Sunday morning, so I was really able to engage a lot with the campus outside classes. There are certainly “flaky day students” (i.e. those who just go to class and leave), but IME they are few and far between; the campus experience there was so all-encompassing that even as a day student, I pretty much only went home to sleep, and I would say the same was true for most of my peers.
I wouldn’t say that a day/boarder divide existed at Lawrenceville to any meaningful extent (i.e. beyond playful jokes)