It’s hard to explain until you experience it, but every boarding school has a “bubble.” The more rural a school’s setting, the thicker the bubble. While right now you think you want a less rural setting, you may be surprised at how satisfying “life in the bubble” can be.
Also, life at a boarding school during term time is very intense. The amount of work expected is staggering. Students love “sleep ins” because they need the sleep. The formula for keeping hundreds of teenagers safe and productive is keeping them very busy. So there isn’t a great deal of time for off-campus adventures.
And yes, schools vary in how many students stay on campus over the weekends. There can be an upside to students heading home for the weekend–often they invite friends home. It also gives the pressures of living together a chance to simmer down with some time away.