it seems nothing runs directly from the wall correctly, but odd story..
I bought a bunch of 6 volt switching wall warts from china, to run though didode to LDO 5v regulator for a personal project
After some buyers remorse while they were in the mail I checked all my little switchers, cellphones, tablets, cameras, cable boxes everything
the little 1.20$ 6 volt warts I got were the only ones that even bothered to copy the UL logo, and on top of that provided a UL number (it could be for a toaster for all I know)
I have had one nailed across a very low resistance, high load for a while now, nearly maxing out its rating ... stupid thing still measures 5.99 volts, go figure