I just wait until I get home or stop in past my unit and clean the car. I never really go any distance with the golf so it's not really a concern.
My problem is that I work a good few miles from work, and the car is parked outside albeit in a car park. My issue is in hot weather. I once went out for lunch, came back and car was covered in bird lime. It was stonkingly hot and despite it being there only for maybe 1 hour, it had already toughened. Soak it loads until I could just wipe it away. Couldn't bear to leave it on for any length of time. Also live on a main road so getting out the PW and SF isn't easy.