[Atroxide]

I am assuming the ad offer would take many things into consideration. the main one being distance, I doubt you could really use such a feature to actually get to somewhere you need to go.

I would also like to point out that every ride they give, and every offer a customer uses, they are getting that much more data to create better behavior guesses which will help show the ads that would be used instead of abused. I also could see this being offered only after you have put in a destination (and thus also your credit card which means you actually need transportation) and if you are going to an area with a ton of restaurants at 5pm, it might instead suggest a restaurant (not near the destination). this couldn't be abused as easy.

I honestly don't see a way this couldn't be profitable in the long run knowing how Google uses all of their behavior data. (this all really depends on the car being self-driven)