surprisingly some of the most well off and well travelled people live in this small corner of the UK.
Whilst that is very true, I doubt if there would be sufficient volume to give good yields on a long haul service. EK would only be able to attract high yield traffic to destinations where going via DXB is not too much of a diversion, and most of those well-off people would prefer direct flights where possible and would not be constrained by budget to fly via the ghastly hub of DXB. They would also have to do something about the squalid conditions and long queues at STN.
Friends of mine who are extremely wealthy and travel a lot never use Stansted, despite living very close to it.