At the theatre this evening (School showcase event) I was subjected to a textbook case of "manspreading" - his legs were wider than the back of the seat in front, with his knee pressed again mine which were straight in front of me.
Rather than shuffle over as I would normally do, my knees stood their ground.
After a few minutes Mr Manspread not only moved his leg away from mine - at a break between two pieces on stage, he left!