You shouldn't ditch someone you have plans with.
James promised his friend that he'd attend his improv show, then won free tickets to a concert on the same evening.
James wants to go to the concert.
James scalps the concert tickets for enough money to buy tickets on a non-conflicting date.
James tells his friend that he got sick and can't come to his show, instead going to the concert.
James goes to his friend's show and loudly applauds his performance.
James' friend sees his concert photos on Facebook and gets mad at him.