Before there was indoor plumbing, there were what was known as "chamber pots" under every bed in even the finest homes. This is obviously a guest stateroom...an en suite "chamber pot" for overnight use makes a lot more sense than a guest having to fumble around in the dark to navigate to a head compartment and then having to find the light switch. Just getting out of the upper to use it would be enough of a challenge for a lot of people!
Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein