Yes Rt one is busy-ish but in 34 years I have never seen anyone going 80mph on it. Thats hysterical. There are stoplights every few miles. You would just get to speed and have to slam on your brakes. I drive it 7 days a week at least twice a day. South County is pretty heavily populated along the coast. Anything further west would be more rural. I can't think of an area that would be further than 15min from a grocery store until you get south of charlestown/green hill.
There's not much year round in charlestown- lots of summer homes and the charlestown mini-super, of course there is a dunkin donuts, they're not totally uncivilized down there
But seriously- wakefield is year round and a real town- there's nothing in Charlestown.