Bill, it happens a lot, both ways.
I had played the Elk's Club here for 15 years or so as a SINGLE. A few years back, they got a new entertainment guy and all of a sudden they had to have a "whole band".
They got a series of them, mostly bad. Crowds fell off, members called me saying come back. I told them it wasn't my decision.
They finally called me to come back, but wanted me to cut my price by 75 percent, because they could get a "whole band" for what I was charging. Needless to say, I haven't been back. Now they have stopped entertainment completely except for a few special occasions.
Same thing happened at one of the VFWs; after having me once a month at their weekly dance for many years, they hired a duo who stunk up the place. Then they decided it was because they didn't have at least four pieces. I still do a few private parties there and the place never fails to fill up. Still they only hire "whole bands" for their weekly dances.
I don't really care; just relating that it's usually one person or a small committee who makes the decision and often it's based on wrong information or personal friends in the "whole band".
Of course, I've taken many jobs from those same bands at other venues, including the one where I have primarily played for most of the past 20 years, and yes, I make as much as the "whole bands" did.
Sounds like you're doing just fine, and getting keep ALL the money. Great, isn't it?
DonM