In my job (I am Credit Manager along with several other jobs in my family's business), I run into people like this all the time. They try to intimidate and push to get what they want (your money). Most are blowhards they've just never had anyone stand up to them and say "NO", starting at a young age with their parents/school/etc. Eventually you just learn that you MUST have a stronger will and not allow their intimidation to succeed. I'd have denied service just out of the principle; not worth the $$. May have done yourself a favor because you KNOW he'd have found something to complain about as an excuse not to pay. You are totally within your rights to deny service (not discrimination to deny service to a azzhat...), and I thought you maintained your composure just fine.
I had a guy tell me once, after I'd denied them credit for poor payment habits,"Don't you know we are a Fortune 500 Company?" I said, "Sure, so you've got less excuse than most to pay late as you have access to capital that others can only dream of" - I think that company was broke in 3 years.
I also had a guy seriously tell me once that "Don't you know writing bad checks was part of doing business?" I laughed and said, "I don't know what business school you went to - Box_of_cracker_jack_U - but I guess that's the day I skipped class"
Lastly, had a guy once tell me he was gonna come down and kick my azz....I gave him detailed directions (my Dad taught me that one)...and spent the rest of the day nervously watching the door
What I continually fail to understand is the girlfirend...her choice in men somehow apparently got twisted early in her life..it's a shame and I truly HOPE I can steer my daughter clear thru THAT minefield.