In 2008 a very large number of Chelsea and Man Utd supporters managed to travel approx 1,500 miles to Moscow where EU airline freedoms do not apply. Contrast 2 very wealthy countries (the UK and Germany are still rich compared to most of the rest of the world with a transport infrastructure that is excellent (even if some still moan).
Airlines are laying on extra capacity without needing to be prompted. The Eurostar can carry 800 people per train from Brussels. London coped very well indeed with the Olympics. If a football supporter in Germany wants to come to London next weekend it will not be difficult.