The WTS senior cultists scour every single human practice in order to further ingratiate themselves into the cult persona.
Case in point is the aforementioned clinking of glasses.
One particular cultist leader (that is, an Elder) who, prior to, had somewhat of a successful business practice, at least once year, made a practice of commenting at KH meetings about business lunches whereby he declined to clink glasses with his worldly companions, and thereupon commenced detailing the horrific Satanic origin of the practice, that is, to chase away demons (shriek), as per WTS teaching.
However, what is of interest in googling (damn that Satan for creating Google) the actual origin of clinking glasses. ( https://www.google.com/search?q=why+clink+glasses&ie=utf-8&oe=utf-8 )
(Brought to you by WT - we put the BS in WTBTS )