As an aside, one of the reasons for so many devices running on "wall wart" cubes..... anything running on 120 VAC has to be listed by UL or ETL or CSA. That listing process requires design considerations and many thousands of $$$$$$$$$$ for the application and cert. process. So you make 60 gazillion warts, which you get listed. The 12 volt device they feed does not require listing.
Follow up: I noticed that my DSL modem, 12 volts, IS UL listed. That may be because it is also connected to the phone line. Or, I may not have the whole story straight! I am blaming the chemo~!