Live near the ocean and the wind will coat your car with salt every day. My uncle lived in Florida on th east coast on the man made canals and his motor home ended up with all the windows facing the ocean welded shut from corrosion. And the winter is worse than the summer because of the salt water dew that gets deposited on the whole car including the frame and brakes. Park a G body on grass for an extended period and the moisture coming from the ground will rot out a frame and under body of a car. The desert is the place to be and you'll get your car sandblasted for free.....
Shore environments are harsh on cars too, seen plenty of rust on the boardwalks. Salt is simply bad for cars. Not sure about parking over grass as both my Regal and Ranger are parked on grass. Don't have a fancy paved driveway, just a mud path. The Regal is still pretty clean while the Ranger being winter driven had its rear spring shackles rust out, rear brake line rust out, ATF cooler line rust out, bottom front of the bed is gone, and rust damage on the radiator support. It has one year old shocks, clean all summer, then got rusty after their first winter.
Also have a 1946 farm tractor, it is also kept outside, battered by farmers for most of its 70 years, and doesn't have rust holes in its sheetmetal.
I know up in northern Canada they often use sand instead of salt which cuts down on winter car rot. Down here in the Mid Atlantic states, DOT does not use sand, they use either salt, brine, or calcium chloride (same stuff you put in swimming pools). They coat the roads solid white with salt at the slightest risk of snow which really rots out the roads, bridges, and over passes, leading the roads to be in constant bad shape with constant repairs in warm months causing jams. As a added bonus the salt poisons the soil and kills most plants off by the side of roads except for poison ivy which loves it.
