speeding ticket in spain on toll road - advice on payment?

Same thing in France - we just paid up (easy to do on their website) and accepted it as part of the cost of a driving vacation.

Would you expect somebody from Spain who was caught speeding on the Interstate to "let it slide"?

That will be your answer.

When you do decide to break the law by ignoring the ticket, expect, some time in the future a knock on the door or an unpleasant letter in the box.

It's a matter of ethics, don't you think? You broke the law, you got a ticket and now you should pay it. If you got a ticket while driving in other than your home state in the USA, would you ignore it? Would you advise a tourist from Spain to ignore a speeding ticket in the USA?

Why do you think you have the right to even ask this question? Do your ethics and morals stop working outside the borders of the USA? Or do your ethics and morals even work within the USA?

If for some reason you decide not to do the right thing, you should know there have been reports, mostly from those traveling in Italy, that collection agencies can get involved with unpaid tickets. That is no guarantee that you would hear from one, but if you did, it would only add to the cost of your ticket.

You will probably also get a charge on your credit card from the rental agency. Most have contracts that stipulate they will charge you an administrative fee for providing the authorities with your contact information.

Please just pay it. That way it will be off your mind and you will know you have done the right thing.

Wonderful
How can it be "impossible" if there is "one" capable of doing it?
Improbable is more likely.
Smile, Wonderful, Smile!
I only seek to bring a bit of a smile in posting about this.
;)