I recently travelled by a Stena Line ship.
A frequent card traveller (Gold) had failed to book a seat in the premier class.
This comes free to them with the card status but everyone else pays.
Anyway this guy had not booked a seat and the premier lounge was fully booked. When told this he started to make an enormous fuss about being refused access to the premier lounge. He was demanding this and that and slagging the lounge staff off something rotten. He made such a fuss that the lounge staff decided NOT to let him enter even though it turned out later that they could have made a space for him.
He stood outside the lounge access door and basically berated the stewardess every time she came out of the lounge, or someone entering let him in, and he argued vehemently with increasingly senior members of the customer services team outside when not doing this. The premise being that he was "entitled" to the lounge access irrespective of whether it was full or not by virtue of being a Gold Card holder - even though access is restricted by capacity and everyone must book even Gold Card holders.
Anyway, my lady travelling companion having listenened to this guy berating the young girl went up to this chap and told him to leave her alone and to stop as he was now disturbing other lounge passengers - much to the pleasure of the Customer Services Manager who by now had been summoned along with the Chief Purser.
On hearing this guy stating that he was going to complain about the attitude of the staff and effectively suggesting that she should not become involved, she turned to the Chief Purser and requested that the man be removed for causing a disturbance, and that SHE would be contacting Stena Line to complain about the man, demanding his name from him by then, about his aggressive and unwarrranted behaviour and his harrassment of a young girl steward.
The Chier Purser took her to one side and siad, "Thank you madam, It would be very helpful if we can take your details as an independent witness - and by the way said
gentleman has now been completely permanently excluded from all Stena Line ships as of now"
Some organisations do have the balls to deal with agressive passengers.