When you use the Papa John's UK app, after placing an order, you are presented with a screen where they "force" you to join their partner programme for 15 pounds a month. The phrase "You order is complete" clearly states the end of the desired action, and the "Continue" button is placed there to force you unconsciously to take that step. Usually, the "Continue" button would move you to some summary page, but here this pattern is used to lure you into a paid subscription.

Image by Sophia Exintaris