IFRS 9 Own use exemption (Q3b – December 2015)

Hello

Please explain the own use exemption in IFRS 9 using an example.

I read that “this is where the purpose of entering into the contract is to meet the entity’s expected purchase, sale or usage”….but wouldn’t this be all contracts since they would all affect a purchase or sale?

I was looking at Q3b – December 2015 when i came across it and the answer provided was confusing.

Thanks