I searched for the Ice melt product on the mountain hardware web site, the description says it is over 50% potassium chloride with sodium chloride (salt). This would most likely explain the salt taste.
Being from back east where they actually know how to clear the roads of ice to keep the number of injuries and deaths down on the roads. I am pretty sure that the amount of salt used is not much because salt actually melts ice and snow, the stuff they spread here does not even compare. And IMHO, cinders are less than useless. I am wearing my shield so you can all start lobbing at me, but some salt would have saved that girls life a couple years ago! And if you take care of your car and wash it more often in the winter, the few days a year salt would need to be used up here would have no effect on cars at all. Roads in the midwest may have salt spread 3-4 days a week for 5 months, we may get a few good snowfalls but not even close to the below zero temps and weather where cars are being effected by salt.