This was mostly a weird scenario that I encountered in one of the three-hour Br34k Gaming servers.
To put it simple, I was playing on a no-money scenario, and on a couple of mazes that I touched up, I noticed that no one would go on them because they "Wouldn't pay that much" despite there being no funds in the scenario whatsoever.

Notice the lack of a Money tab in the ride window.
This should only happen on no-money scenarios that started as a scenario with money, and got switched. When those mazes were built, was the game already in 'No money' mode?
From what I remember these servers always start with no money, but I believe the original scenarios featured money in their objective.
Yes, but did you build those mazes now, or were those there when the server was started?
The latter.
I've noticed this in a number of my own parks. Starting the game with money and then switching to 'No money' will cause guests to think the rides built before switching still cost money, and will react with thoughts like "I'm not paying that much to on [Ride]" regardless of there being no money. This can be replicated in any park that starts with money and has rides in it.
This should really be marked as a bug.
No easy way to solve this other than to go through all the ride->price and ride->price_secondary in peep.c and make sure it checks for no money flag. Some places do already check, but not all of them.
or when you switch.. set all the prices of the rides to be 0
I prefer Joshwoo69's solution actually: it avoids littering the code base with many checks for the No money flag.
If you change all the prices to 0, then players can't change the money flag temporarily - which I expect will be a common use case.
yeah.. then you would have to keep the original price... like somehow...
So two options then: Check for No Money Flag, or 0 all prices (and store them somehow).
It seems to me that checking for the flag would be easier to implement and less prone to bugs (outdated lists etc).
That will be a check for No Money flag, then, if we want to support that use case.