At least in my town it was the banner of the communist party at the very front of the demonstration. Followed by some music, followed by their student wing, followed by a womens rights banner, and somewhere back there were the socdems
In my country succdems are cartoonishly anti-communist of the “evil totalitarian Stalinists just as bad as Nazis” type.
May Day parades here are usually a brass band at front followed by union banners. The unions here are all solidly succdem controlled btw. Although formal ties were severed a long time ago it can be very hard to see where the Social Democratic party stops and the union bureaucracy starts.
Then there are speakers. Usually a union guy followed by a politician from the Succdem party, one from a smaller “succdems with wind turbines” party and lastly one from a “revolutionary socialist in theory but actually supporting the succdems blindly because the alternative is too scary” party. Then everybody gets drunk and goes home.
