It was planned. Here is the press release.
On Saturday 8th September 2018, the Last Night of the Proms, the greatest annual party in classical music, concludes the summer-long series of promenade concerts staged by the BBC at London’s Royal Albert Hall. The event is traditionally associated with the performance of patriotic tunes and the audience exuberantly waving flags of all nations.
In 2016, following the European Union referendum, a number of prommers were concerned in case the Last Night was hijacked and used as a jingoistic celebration of Brexit. So a group of music lovers crowdfunded a large quantity of EU flags to be waved alongside the Union Jack. We were keen to demonstrate that it is possible to be patriotically British at the same time as maintaining a European and internationalist identity. We raised £1,175 from 60 supporters in just 28 days, and our flags were enthusiastically welcomed by the Last Night audience. In 2017, we more than doubled our £2,000 target, raising £4,218 from 248 supporters.
So this afternoon, for the third year running, the EU Flags Proms Team will be at the Royal Albert Hall, handing out 20,000 free EU flags to members of the Last Night of the Proms audience.
Next year we will be partying and celebrating the UK coming to its senses.