Here’s two true stories directly relevant to the principle which is the fundamental concern of the original poster.
A little while ago, a major internationally famous singer and band, with many chart hits under their belt, launched a worldwide tour.
Everything went smoothly for a while, but whilst they were in a relatively small country, the sound and road crew were suddenly called to a meeting.
They were told that henceforth, they would only be paid for days that were actually worked, contrary to pre-existing agreements. Travelling days, waiting days, odd days thrown up by delays, time taken to get to airports and hotels.
Everything that is a naturally occurring part of touring across countries and continents that takes time, they would no longer be paid for. Only set up days, breakdown days, and performance days would be paid.
Whilst it’s easy to claim that contracts existed and compensation could be sued for later. It appeared that the time this was dropped on everyone, is when they were relatively isolated physically and electronically by the nature of the situation, they were in. Cut off from their natural systems of support.
Effectively they were faced with a well-prepared fait acomplit, accompanied by persuasive reasons why they should accept the new contracts they were presented with. A somewhat smaller loaf than they expected, is better than no loaf whatever.
After all, they might want to work in the same industry on future tours. Did they really want to be blacklisted by kicking up a fuss? Better to accept the new deal.
All this with no time given to think and consider, the tour has to move on to the next venue!
True story number two.
A little while back, a nearby local factory had been taken over by a large corporation.
They made much needed investment, and the existing management and workforce reward that with resounding commercial success.
Commitments and agreements were made for career development for high flying managers who were given firm expectations regarding their future.
But the large corporation would regularly rotate management personnel, Plant Directors and the like. An incoming Plant Director threw out all the commitments and agreements their predecessors had made.
Initially this high-handed decision, grievously affected the future career paths of a large slew of highly successful managers who were well used to working together. But one of them was extremely well connected, and decided to act for the benefit of the group.
Elon Musk came here to speak.
He was head hunting, and after his talk and the question-and-answer session that followed, the whole group of them went to a local college, the Dean of which was a friend of Elon’s.
They all enjoyed a slap-up meal together, after which Elon offered them all well paid positions in his Space-X company. So, at the drop of a hat, the new Plant Director found over night that the entire staff of executive managers that effectively ran the huge factory, were leaving for new careers in America.
The Plant Director and the factory he was in charge of was left in utter chaos!
Here’s the talk that the managers attended.
Which includes the Dean whose college they enjoyed a meal together at and where they received the job offers.
Elon Musk - the Future of Energy & Transport - YouTube
It appears to me, the woman who has attempted to renegotiate the bands remuneration, has done so for one of two reasons.
Either the reduction has been attempted to increase profitability to the business, which as a new comer is effectively a feather in her cap, and might even involve a bonus to her personal remuneration.
Or, by renegotiating the fees already agreed with bands which are known to the venue owner, its possible that she could keep the difference herself if the owner is not closely involved with that part of the business.
Owners hire managers so they don’t have the bother of dealing with such matters.
Either way.
It is clear to me at least.
That rewarding such behaviour is the wrong thing to do.
The right thing to do, is to call time on it, making it crystal clear it won’t be tolerated.