nag 'n brag
Complaining about something you paid for like a service or a flight. Then you get a free drink or a discount and you brag like you won the lottery.
I paid $200 for my flight and got bumped to coach. Then I got a free beer and now I'm telling everyone I'm a flight god.
My barber cut my hair wrong, I yelled at him, and now he gives me free haircuts every week. I'm like a hair king.
I complained about my pizza being cold, got a free dessert, and now I brag like I'm the pizza queen.