Rival and non excludable products I learnt that if the service provided is of non-rival and non-excludable in nature, the problem of free riding occurs and the provider may not get a profit. I can understand how non-excludability results in free riding but I couldn't uderstand the effect of
  non-rivalry. In the book I read, street performance was cited as an example for non-rival and non-excludable service. The following is an excerpt from the book 'Day to day economics' by  Satish Y. Deodhar


  at a given market price, the relative buying power of different consumers might exclude some of them from buying the car or the toothpaste. In the case of the street-performing couple, this ‘excludability’ feature is missing, because they cannot prevent individuals—either physically or by charging an appropriate price—from viewing the performance. Thus, due to the non-rivalry and the non-excludability of the service which they provide, the problem of free riding occurs, and the market fails to deliver—ergo, the street performers cannot run a profitable business.


Is there any service that is rival and non-excludable? If so, how is it different from the previous case with regard to free riding?
To continue the example of the street performer: 

Suppose there are two people offering the performer money, but in exchange they want her to perform different songs. Person A prefers song A while person B prefers song B. Whoever offers the higher sum gets their wish. In this case there is rivalry between the consumers. Yet there is also non-excludability: Even if someone loses the bidding war, they can listen to the song chosen by the other person.

Note that the rivalry results in higher profits than if both people preferred song A played, because then they would have had no incentive to bid against each other due to non-excludability.