I'm much more tolerant than you are.  (You've probably noticed.)  I don't mind removing items from envelopes, and I manage to toss out the empty envelope even when the client is in the office, by diverting their attention for a moment.  The only ones who enrage me are the end-openers.  Envelopes are meant to be opened along the long, top edge.  Research has shown that most heroin addicts and mass murderers, started out opening envelopes on the short, side edge.