Recycling sand on roadways is just about impossible as traffic running over it tends to round the sand particles which makes it act like marbles and does not help as much with traction. It also creates a ton of very fine particles which turns to mud.
Sand/salt mix works well on gravel roads - particularly right after application as the dissolution of the sodium chloride is endothermic (absorbs heat) and can cause the road to ice up temporarily.
Every state has different application rates, but the use of straight salt does increase the amount of salt used some, but it is not as much as most people think, since the salt in the sand was doing the work for snow and ice removal so you just had to apply a lot more material to get the desired affect.
When CT switched from a sand/salt (de-icing) mix on state roads to all salt (anti-icing), the number of crashes occurring on roads with snow, slush or ice was significantly decreased. The idea of anti-icing is preventing the bond of the snow pack to the pavement which ultimately requires less salt to get the pavement bare at the end of the storm. The idea is to maintain a layer of brine between the snow and the road. For salt to be "melt snow", it needs to be a brine - dry salt does not affect ice.
And for what its worth - salt (sodium, calcium or magnesium chloride) does not damage asphalt pavement. The same can not be said for Portland Cement concrete.
I will apologize for the dissertation on winter operations - it is something that I have spent a lot of time on.