The period of socially acceptable time after a purchase, in which to freeload.

For example, time in which to use wi-fi / tables / sockets / toilets in a coffee house or restaurant, which extends from the point of ordering of a meal or drink, to the point at which one is asked to leave or the (usually justified) passive aggression of serving staff becomes a distraction to work. Length of time is proportional to value of the purchase, size of tip and quality of your small talk or flirting, with said staff.
Bustling pointedly past my table for the 25th time in 10 minutes, the waiter eyed me unpleasantly and loudly mentioned to his colleague about how busy it seemed in here today. The purchase halo of my small filter coffee had long since dwindled below the locally acceptable dimensions: we were in the end-game now.
by coffeecoffeeblahblahblah September 9, 2018
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