The price of flying from the UK, Heathrow in particular, is influenced on the charges such as fuel duty, APD, airport fees etc etc. which make LHR an expensive airport to start a journey. If on a connecting flight your first portion is short haul then the costs reduce dramatically, When I lived in Holland I discovered that a) if you travel via London it was cheaper than flying directly from Amsterdam and b) when using KLM starting from anywhere else other than Amsterdam, even thought travelling through Amsterdam, was cheaper than starting from AMS, when I travelled to Ecudaor on a photo tour starting from London it was made clear to me that I should join the club even though the long haul flight originated from AMS, I lived 20 miles south of Schiphol at the time. Imagine the confusion when I checked in my luggage, but you are joining the flight in London Mr Jones? The £29 bmi flight to LHR was much less than the premium I would've had to pay if I didn't fly to London... And you think rail fares are confusing.
Business wise, flying to the US, it was cheaper for me to use BA than fly direct with UNTIED. really enjoyed my Club World journeys, did get bumped up to 1st once.
Still I met my other half at Wetherspoons in LHR T4 when meeting the group, 18 years ago! Everyone thought it was strange I'd flown from Amsterdam that afternoon, only to go back that evening.
The flight was on a lovely MD-11, to Bonaire, Guayaquil and then Quito. Luggage was waiting for me (as were my 120 films).
As for B-word, I travel quite a fair bit and the only difference about not being able to use the EU E-gates is the potential to land just after a long-haul 777 or A380. Munich it is bad but not so bad in Venice or Hamburg.