Any profession with an automated 'customer care' line.
These things always have people on the other end that have very strong non-english accents when I need a bit of customer support, yet i'm expected to understand them when it sounds as if they have their headset on the back of their head.
However as soon as I forget to pay something then I get phoned by the person with the crystal clear british accent of someone that went to the same finishing school as Mary Poppins.

My Bill is outstanding is it??
Why thank you very much. - someone I can't remember.
(Mensa Reject has gone out, I'll be back on, Fri 28 May 2010, 2:12, Reply)