I don't shower at the gym frequently, if so, then in summer only.
Although I sweat a lot during exercise (especially in a Zumba or spinning class), I don't worry about getting into my car. Typically, I sweat a lot more on my upper body than on my lower body and I always wear gym pants, so I don't see why not. I always go straight home from the gym to shower, I have fine hair and unless I wash my hair I will look like I emerged from the sewer.
Fortunately, it takes me 5 minutes by car to get home - sometimes less, depending on the traffic lights - it's a short distance but I have cross three intersections with traffic lights.