Bocksbeutel

These sacks were used already in pre-Reformation times, but became eventually outdated and were seen as a whimsical expression of overly conservative behavior.

Another claim is that the term actually means "ram's scrotum", which is supposed to be of similar shape as the bottle.

If the Low German term was adopted in Franconia, any similar local words are likely to have influenced this process.

the "Kick me" prank, cuckold horns and other forms of public humiliation such as "donkey ears"), but a wine bottle is an unlikely object to use for such a purpose.

Both a Booksbüdel and a ram's scrotum are perfectly suitable, being small and light objects with a connotation of ridiculousness.