I'm a Londoner and could sort of see where the programme was coming from. The staff were quite typical of some of these famous places and the guests seem to like the chirpy chatty style. My friend and her husband stay there every year for their wedding anniversary despite only living 6 miles away.
I've stayed at various London hotels - The Waldorf, The Hyde Park, The Curzon, Crowne Plaza, Premier Inn - they are all different and have their own character. I think maybe the more discreet ones wouldn't make such good TV in terms of the humour.
Yes, it was sad at the end and a bit eerie I thought.