Yeah mine worked fine. This one is right near the entrance and these guests are coming straight in through the entrance - so have all their money.
Have you checked to see if the guests explain why they turned around ? Some guests complain about the cost, others might have run out of money etc.
How far from the entrance is your one ? Any ATMs close by that they can utilise before going in the store etc ?
Also, it is possible that they are already on a task that can't be rescinded. As we found out recently, queuing immediately stops any other interaction, even reading the educational screens alongside the queue.