I think he was upset cos a girl band was chucked in jail for singing in a church. If it had happened in UK, the cops would have removed them and let em go or not even have responded at all.
And here starts part nor Mark or general public don't know. Those girls are actually experienced troublemakers, they did not only singing in church, one of them once had s*x somewhere in public, while being prengant, they had another bad 'concert activity', this singing in church was just a last drop. Not talking about their music being pure dog's food, they're punks in the most disgusting meaning of the term.
And what Mark reads? 'Three poor Russian girls being thrown into jail for 2 years!'. And thinks 'I'm gonna cancel the tour over there'.
He cancel the tour in Russia because he admires girls who had s*x in public while pregnant or something like that? He should know the whole story first.