Emily Skinner -- 2 Different Productions of Dirty Blonde?

In theatre you don't see it quite as much just because you often don't see major stagings as close to each other. Now, go over to opera and it's a whole different story. There you often have singers closing one production, Carmen for example, to maybe have a week off before going to another company to do an entirely different Carmen. This is part of the reason that is given for stage management to have to cue singers' entrances so much more heavily than they ever do in theatre.

There are plenty of actors who repeat roles frequently in regional theatre. The cast of every production of Miss Saigon comes to mind...