This is one aspect of the game I just don't get. Why would anyone refuse to go on a ride because the physical length of a queue is too long? (I don't even make them that long, maybe about 10 clicks of the shortest queue length or less). Even if there is barely anyone else in the queue they will just refuse to go on it.
The other annoying thing is that this even happens with the rides already placed in career mode. So the guests aren't even happy with Frontier's queue length placement. I've had to go through each one and shorten the queues to make the guests happy and ride them again. Hopefully this is a bug or something or will be changed because it makes no sense the way the system currently works. I would say fair enough if I made mile long queues or something, but like I said I've kept mine pretty modest.
Also I wanted to note, I haven't changed the ride sequences or anything to make the ride take longer, I've kept them all at default.