I charge them more on any subsequent jobs for what I term "hazardous duty
pay."
I also give a heads-up to other contractors. :-)

I introduced the "ass*ole tax" concept to a younger electrician I knew.

People that worked for the same corporation, although they had by various
means, put the screws to him (including one that tried to get him fired)
would take others recommendations to hire him for personal jobs and then
they'd -expect- to get a 'staff discount' on his bids.

I told him IF he was going to bid their jobs ( I wouldn't have) to calculate
his fair price, and THEN ADD $ 100.00 A-H Tax to his final bid..
He had numerous folks ante up the TAX.
This was about 20 yrs ago..AH tax has obviously increased now.