Trend initiated in Germany in the early 2010s, originating from the older rural hospitality custom of sending a guest home with a jar of pickles or other preserves. The recent modern practice of including a pickle with gifts of gratitude or invitation has been popularized in western European countries, the US, and Canada.

Earlier related adoptions in the west (US/CAN) include pickles accompanying deli sandwiches or other 'working man' lunches (particularly common in the US tri-state area, given the large European immigrant community).
Bro! You got a postal pickle?! That's so sweet, she must really want you back...
by postalfiend62 August 18, 2019
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