Do you have some musical theatre gift vouchers that you were given as a present? You can use these to go to any show that you want to see at the theatre at which they were purchased. When you go to get your tickets, they are just as good as money. You will not be asked to pay anything unless the vouchers are worth less than the price of the tickets that you want, in which case you will have to make up the difference.
However, the fact that they can be used as money does not mean that they are actually worth money in a general sense. You cannot go to the box office and ask to cash them in. There will be a note somewhere on them that tells you that they do not have any cash value. This is done so that the theatre itself does not have to give out money to people who have decided months later that they do not want to go see a show after all. This also acts as a deterrent to theft because thieves know that they cannot get cash for the vouchers.
If you do not want to go, the only option that you have is to sell the vouchers to a friend. He or she can pay you for them and then use them to get tickets. This really is a situation in which both you and your friend will be happy. You will get some cash that you did not have before by selling something that you did not pay for in the first place. Your friend will be happy because you can sell him or her the vouchers for less than the value that they hold. This gets your friend into the show for less than normal. You are still not out anything because they were a gift and you did not invest your own money.
