Yep, most are. In fact CGI effects studio The Mill have a shell of a car that can expand/contract to fit the proportions of most regular cars, that can record its surrounds enough to build the environment for rendering, and that can be driven in place of the real car when shooting.

The car being advertised is then edited in over the top, using the recorded environment to ensure accurate lighting and colours.

http://www.themill.com/portfolio/3002/the-blackbird

That's really cool! Here's a video with more details:

https://www.youtube.com/watch?v=OnBC5bwV5y0

I noticed the CGI cars in this clip don't have drivers in them.

How would they add a driver for an actual ad? I think cars are much easier than humans to do photo-realistically in CGI. Or do they just show the car in a way such that you can't see that there's no driver?

I'd assume they'd just use window tint if they're cheap, or the same stuff used in movies to drop actors in if they're not.

Wow.

CGI is not lying. Faking photos as a demo of the camera is lying.

Depends on one's definition of lying, I suppose. At the very least CGI car ads are implying that you're watching the actual cars being sold being used in the various situations shown, when in actuality it is a generic rig that a CGI image has been stretched over.

I don't know that it materially makes much of a difference or really matters for car ads... as long as the cars shown can accomplish/look like in reality what they appear as in the ads. Still yet I think the intent is to have the public believe that they are watching video of the actual vehicles, in which case, one could call this "lying" in some form (whether or not we want to ascribe any particular moral bent to the term)