Aedile
Governor
Of course I could see a starving actress going through with it for the money, looking for her big break.
I remember an interview with this particular Spartacus actress (Laura Surrich), where she said she regretted taking this role because it killed her career. Looking at her IMDB, it appears she was right.
In the reverse situation, Rachel Sterling danced in strip clubs and did some softcore porn before trying to get into acting. She almost got scratched from being cast as the dancer/courtesan Assia in the otherwise forgettable “A Man Apart” because a producer recognized her. Luckily the casting director went to bat for her, and she ended up producing one of the most sultry performances I’ve ever seen in a mainstream movie (especially the full, deleted scene!)