I do not care whether the audience stands to clap, dances in the aisles
or otherwise shows its appreciation.  (Personally, a Mexican wave after
Swan of Tuonela suits me fine.)

BUT

I do object when they throw flowers (normally from the choir stalls
behind).  Do they know what a flying chrysanthemum can do to a $x,000
instrument?  Let alone when the roses go down the contra tubes ...
(Poor fellow is still in tears...)

CR