I thought it was the other way around.
If they have trade on board they have to respect lower limits as I understood. I thought there was some leniency around red lights for a train of cars in a funeral procession. In NL they hand out red mini-flags you place on your side window which helps the procession move. People there are kind enough to stop and let you through as a group when they see the flags.
Last biker funeral I went to, they let the parade of bikes pass without interuption. No need for little flags. Big turnout - there must have been easily 60 bikes.
