Amateur theatre groups throughout the UK are facing huge losses following Denmark's decision to ban Marmite.
Community centres and civic theatres up and down the country are currently advertising performances of Shakespeare's Hamlet but authorities fear they cannot go ahead.
Police were called to a community centre in Keighley, West Yorkshire, last night when crowds gathered in protest at a performance of the tragedy set in Denmark. People trying to see the play were "jostled" by protesters at the box office, according to reports.
"It's a bloody disgrace is what it is," said Norman Git of nearby Silsden. "Bloody Danes banning us Marmite and then expecting us to just roll over and let them have a play put on under us noses!"
There were similar scenes around the country - windows were broken at a civic theatre in Hemel Hempstead and amateur actors were threatened outside a church hall in Tipton - although they were due to perform Webster's The Duchess of Malfi.
Said Tolliver Marlowe, chair of the Let's Do The Show Here Trust: "This is a potential disaster for amateur theatre in the UK. Our members are doing Hamlet out of the goodness of their hearts.
"A Hamlet or a Richard The Second can pay for an entirely crap season after no-one bothered to come the Whitehall farce or the local writer's effort to dramatise War And Peace!"