What are the disadvantages to using salt/sand mixture on the road?
It corrodes your car pdq..........
Some of the older used cars you buy and see on the North American continent are absolute rust buckets; the jalopies were only held together by rust. And this results from the splashing of ice onto the panels, where corrosion would be greatly facilitated by the presence of sodium and chloride ions. Where I grew up (western NSW), a used country car was known to be superior to a used city car because the city car would have invariably been by the sea, and its panels would tend to be corroded by the salty sea air (the country car would be dusty, sure, but it would NOT be RUSTY - the winters were not so harsh as to require salting and gritting). The reverse applies on the North American continent.