effect of winter on the finish
 

I'm wary of automated car washes and have always hand washed my Audi. I owned an A4 and recently traded up for an S4. In New England, the car washes use antifreeze in the water. I always wondered if the chemical in antifreeze was worth the effect on the finish vs the harshness of the salt and not wash it in automated car washes. So I waited this winter as we got killed with over 100 inches of snow in 6 weeks in Boston. I just washed my car in my driveway today and noticed multiple rust colored dots on the car body and bumpers. Freakin' rust after only 6 weeks of letting salt sit on the finish? I took my finger nail and attacked 3 spots. They seem to have come off but light was dim in the garage. Any one experience this on the finish in harsh winters? I'm hoping next weekend to wax it and hope that, with some elbow grease, these rust color dots (2-3mm in size) come off.