Anyone else experience this? The front discs start rusting from the outer edge yet the rears stay bright and shiny!

This was a new pair fitted last summer but the recent salt on the roads and maybe my light footed braking has them starting to show rusting like the last set. They were changed at about 45k with new pads also even though the original pads still looked like new. Its as if the pads are not abrasive enough to keep the front discs polished like the rears.