A question for the people that drove from out-of-state - am I the only one anticipating the Illinois State Police breaking down my door to haul me in for toll evasion? I have not received any instructions or bill.
Reading between the lines, I think what Chris is concerned about is cashless tolling. This is a growing trend that has interesting implications.
The basic concept is that tolling systems on highways, bridges and tunnels (and related things like parking garages) are designed to work with transponders in the vehicle - when you pass a toll gate, the transponder is automatically read and a toll is assessed against the vehicle owner's account. This is actually a great concept because tolls can be collected without slowing down the flow of traffic while avoiding the costs of having human toll collectors. And in some places, there may even be a small discount off of the regular toll as an incentive to get a transponder and participate in the program. Programs are actually administered by businesses such as EZ Pass or FastTrack, and if you have their transponder, you then are set up to participate wherever they offer a cashless tolling service. So, for example, I live in New York, and travel over into Massachusetts frequently, and my EZ Pass transponder covers my tolls in both states, as well as for the parking lots at our local airport and train station.
The way these programs work is that you pay a deposit into an account, and then charges registered to your transponder are withdrawn from that account as those charges are incurred. When the amount in the account drops below a threshold, the system charges an associated credit card to restore the initial deposit balance in the account. The account owner gets a monthly statement that shows the tolls incurred and the end-of-period balance. In my case, I paid a $25 deposit, and the account tops up when the balance falls below $10.
But these systems have to have some provision for people who don't have the appropriate transponder. Most commonly today, that provision is in the form of automated license plate readers linked nation-wide databases that allow the operating company to send a bill to the vehicle owner. There is usually a service charge added to the bill to cover the cost of manual billing. That obviously can be more expensive than the toll, but I understand why it is done.
But there is another situation that is harder to understand - rental cars - because the license plate is linked to the rental car agency and not to the driver of the vehicle. What can happen in this situation is that the rental car company outsources the toll responsibility to a third-party. This can get expensive for the person who rents the car. Several years ago, I got hosed by one of these outfits who calculated their bill as the sum of the actual tolls plus a daily service charge for each day of the car rental - so crossing the Golden Gate Bridge one time (posted toll was $5) cost me more than $30!
It turns out that sometimes there is an option to bypass the billing company by registering the car license plate together a credit card number and a period of time - that way, your credit card gets charged any actual tolls you incur during the specified time period, but not that outrageous daily service charge. But you have to read the fine print to discover find out how to do it, and then take the initiative to go on-line to register the rental.