Obviously Houdini was right in pointing out this mistake. But there might have been a bit more to it. Junior Orpheum's were a step down from the circuit's main vaudeville theaters. They played three shows a day and a movie. When Houdini played the Orpheum circuit, he played the main houses that presented two shows and kept movies in check. So it's likely Houdini's real sensitivity here was that this made it look like he was slipping down the vaudeville food chain.
still standing), and the second the Hillstreet Theater in Los Angeles (advert right). Both these engagements came a week after his run at the main Orpheum houses in each city. But with his movie businesses draining his funds, Houdini admitted his 1923 vaudeville tour was done because he needed the money.
It should be noted that during both these engagements Houdini was able to present his spiritualism lecture during special matinees. So maybe that was worked into his contact to sweetened the deal and convince Houdini to go Junior after all.
UPDATE: I've discovered Houdini also played Junior Orpheums in Kansas City and Urbana, Illinois.