When Frasier, Martin, and Daphne are interviewing housekeepers, Martin mentioned that when he and Frasier interviewed Daphne, Frasier thought she would steal from them. However, in "The Good Son" (the Pilot) when Martin and Frasier interviewed Daphne, Frasier never mentioned a fear that she will steal from them. In fact, stealing was Martin's concern about the woman they interviewed just before Daphne.
Furthermore, it is unlikely Frasier was at all worried that Daphne would steal from them when they interviewed her, because when Martin mentioned that Daphne would only be in the apartment when Frasier was not, Frasier immediately told Daphne she was hired. He probably would not have been so quick to hire someone he feared would steal -- especially if he would not be home when she was there.