This is an interesting question that I've often wondered myself.
In my experience as a Chicago Theatre goer, the out-of-town tryouts typically have a windowcard. For example, there was a windowcard for Big Fish in Chicago. It had very different art work than the Broadway artwork. There was a windowcard for On Your Feet with the same art work as Broadway. I've gotten windowcards for the Chicago tryouts of Aida (with totally different artwork at the final product,) the Pirate Queen (same graphics, sadly) Kinky Boots had a Chicago windowcard with the same graphics as Broadway, The Last Ship tryout also had a windowcard which remained unchanged until Sting joined the cast, and The Adams Family also had an out-of-town windowcard with the same graphics as Broadway.
Some out-of-town tryouts do not have windowcards at all:
Beaches did not
Gotta Dance, sadly did not
I don't see too many tours so I'm not that sure. However, I did see the tour of If/Then and there was no windowcard. I assumed it was a cost reason as the ones for Broadway clearly featured Idina and not Jackie Burns.