an option to hide items that were not purchased would help to reduce regret and impulses to re-think re-thought purchases, but allow them to contribute to statistics.
this could look like hiding the images and descriptions for ‘didn’t get’ items, but keeping the prices visible. it could be a toggle-able option in settings with a password lock. the password would be helpful as it could be written down and kept elsewhere (e.g. at work or school) to force you to think ahead about un-hiding and purchasing these items. alternately, the toggle could be set to a timer (e.g. 7 days) after which items are un-hidden.