"They strapped on their cauldrons, stood poised to fly,
At the sound of the horn they were swiftly airborne...."
-- translation of Gaelic poem (QA2)
Playing the game involves trying to catch hundreds of falling rocks and boulders within cauldrons strapped to the players’ heads. It inevitably caused huge numbers of fatalities and was banned in 1762 (QA2).
Quidditch Through the Ages author Kennilworthy Whisp wondered whether the “Scottish warlock” mentioned by Gertie Keddle at a game played on Queerditch Marsh had introduced the concept of flying rocks from Creaothceann (QA3).
The Scottish (and Irish) Gaelic word ceann means "head" and the word creach/creagh is a "raid or foray" - or the plunder and booty obtained thereon (Dictionary of the Scots Language).
Somehow flying around on brooms trying to catch rocks in cauldron-topped helmets really does not appeal.... Wizards certainly have a different view of health and safety than Muggles.
From the Web
Harry Potter Wiki: Creaothceann