tip bait

Etymology
. Popularised in the 2020s with the rise of services during the.

Noun

 * 1)  The promise of a large tip (usually on a delivery app) so that the deliverer feels incentivised to swiftly reach their destination, only to deliberately decrease or cancel the tip once the delivery is completed.

Verb

 * 1)  To make such a falsely promised tip; to engage in tip baiting.