my wife DMs. A year or two ago, two old friends of her approached her about all three of them DMing three different groups in a sort of mega game, in which all three groups would be in the same world, tangentially related to each other, with sort of light crossovers, with a plot that would eventually resolve with a mega-session where all three groups would have to work together to defeat whomever the big bad was.
So far, so good. Our group made characters and started the game. We got like three or four sessions in before she told me that, during their weekly post-game wrap up meetings to coordinate, one of the two guys started asking "when do we start charging them?" It turns out he wanted to do this as a backdoor attempt to start a pay-for-play thing to make money on.
When she stated "i'm not charging my party for this" he got huffy and "kicked her out" whatever that means. The other guy also quit and that was the end of that.
We played those characters a couple more times, then moved on to the next campaign.