Posted: 24/11/2015 at 19:20
If you look at the link, they are not actually advertised as a prank. They are grown as a solution to a problem many gardeners come across. They are grown and bought by gardeners (just like we buy and use Nematodes for slug and other pest control)
No mention of pranking. (they even provide food)
PS. the English use of the word pranking is old and means: To decorate or dress ostentatiously or gaudily.
To prank has a different meaning.