Weirdos. Why travel to another country to kill yourself. Doesn't Britain have any buildings you can jump off, or trains you can step in front of?
Hell, just go to a local soccer game and root for the visiting team!
Tall buildings and trains are not a guaranteed way to die. Hit a tree on the way down from the roof and become paralyzed, unable to finish the deed, imprisoned in the mostly dead body.
Also buildings and trains and other similar methods can be used quickly, on impulse, in a bout of depression. However it takes much longer to travel to Switzerland, and once there the personnel will talk to the applicant. More chances to change his mind.
Because the Swiss have a sweet settup with people trained to talk you into the final act? I like the futball angle though. Shoot, just go into any mosk and say Muhammend is a bedwetter! Or draw a picture of Muhammed!! Instant fatwa!
Because Briton had nanny-state laws governing you and your body?