Saltwater corrodes firefighting equipment and may harm ecosystems, especially those like the chaparral shrublands around Los Angeles that aren’t normally exposed to seawater. Gardeners know that small amounts of salt – added, say, as fertilizer – does not harm plants, but excessive salts can stress and kill plants.
In the UK we don’t have any special rules for winter driving but in many parts of Europe they are trained for these conditions and it’s illegal to drive on summer tyres, driving without emergency equipment, etc.