Very interesting. I wonder why they thought the brush and mug would be obsolete by 1930?
I think this is a great reminder of what the times were like back then. Shaving was done mostly at home and there was a palpable push towards modernization in all aspects of daily life. In our hobby this was epitomized by the Burma-Shave roadside ads of the day that frequently ridiculed "Grandpa's old-fashioned shaving brush."
Brushless shaving cream was new, modern, sexy. The barbers could see it coming. Goo was right around the corner, God help us.