I commute daily on my motorcycle, rain or shine, all winter too. The only days I don't are snow or ice conditions (and even then I have been caught riding when an unexpected snow or ice storm happens) SO, for me tire life matters. I don't want to schedule the times to take it in, I work six days per week and the place I take it wants to keep it overnight and yes I have tried three different shops all are the same! Tire changes are a headache for me.
Rain is no reason to take a car in my experience.
What kind of bike do you ride?