I sent out a text with every single ride I accept, telling them that I do not go out of state, and if they are going out of New Jersey they need to please cancel and request another Uber. I explain to them that Uber does not tell as the destination until we actually start the trip. I also tell them that if they are traveling with small children they need to have the appropriate car seats for that.
My experience has been that almost every single time I have shown up at a place to pick up someone after I have sent this text, either they are not going to the city, or I have had the ride cancelled very shortly after sending the text. The part that no one wants to acknowledge tends to be the car seat issue. Everybody thinks their baby is just so cute that I'm not going to be able to say no. The fact is the baby probably is really really cute and that actually makes it easier to say no.
Once in awhile I will get the drunk jerk who wants to go to the city and didn't want to cancel. I show up and he (yes it usually turns out to be a guy that does this) tells me that he doesn't want to have to pay a cancellation fee. I explain to him that had he cancelled as soon as he had gotten my text, he would not have gotten a cancellation fee. Now I have wasted my time and gas getting here, not to mention whatever wait time there may have been for him to show up, and that he needs to pay. Most of the time, when this rare event does a car, they refuse to cancel, so I sit there for 5 minutes and then I cancel for a no-show.