I check-in on FB if I'm flying F for leisure - love a good CCR check-in to make all my friends jealous. I'm famed (and teased) in my family and circle of friends for being a total miles wh0re , so it's my form of payback to demonstrate the fruits of all my labours.
I then follow up with a picture of me looking smug, sipping a nice glass of bubbly in a set of First jim-jams, First slippers and a copy of the Financial Times. They appear to find it amusing....