I always tip the car service driver especially since I am partial to one company that offers the best service that suits my needs. When I book with them for a Lincoln Towncar they always upgrade me to the stretch limo when its available. If they cannot offer me the upgrade they have my favorite cold beer or red wine waiting for me. In the stretch limo my favorite drinks are waiting in the mini-fridge with trail mix and other snacks. They always try to get me the same driver who knows me and where I live etc.

So tipping shows them how much I appreciate their service. They know what I like and where I need to go. The driver is always at my house 15 minutes before the time I ask for and will help me load my bags and meets me at the baggage claim.