The amperage flowing through the switch damages the contacts long before voltage. This means that if the train in the siding is stopped and not drawing any or much power, there is not load on the switch when you make and break contacts. The ratings and the problems occur when making and breaking (opening and closing) the contacts. And automotive applications are much higher amperage generally than model RR so eh contacts would be rated much higher for our appliations.
And example ot this is for years I used rotary switches from Radio shack for block control on my layout. I used the 2 pole 6 position switches and they are rated at .3 amps for making and breaking. I don't know the voltage rating. Anyway I still have at least 2 dozen in service on a 3rd layout and I have never burned one out going through AC, a couple of DC systems, and now a DCC system.
So bottom line I think the automotive switches will work fine for control.
