"an hotel" is just wrong in my experience, which I think is where "people trying to sound posh" comes into it.
The south and the "posh" (there is quite some overlap there as there is a perception that the south is more posh and the north more rough) use "a hotel" which is also technically correct, as you move north the "h" gets dropped so "an" becomes correct, though if you are writing that you should have a apostrophe to indicate the dropped letter (an 'otel) - in fact the 'postrophe is sometimes even pronounced by way of a very small pause (this is often a clue when decided if someone has a particular accent or is just imitating it).
The south and the "posh" (there is quite some overlap there as there is a perception that the south is more posh and the north more rough) use "a hotel" which is also technically correct, as you move north the "h" gets dropped so "an" becomes correct, though if you are writing that you should have a apostrophe to indicate the dropped letter (an 'otel) - in fact the 'postrophe is sometimes even pronounced by way of a very small pause (this is often a clue when decided if someone has a particular accent or is just imitating it).