alt-text: Woman ordering food (photo): “I would like to buy a hamburger for the same price that it was 2 hours ago.”
Cashier (sketched): “Sir, this is a Wendy's”
The fluxuations will be dampened by the fact people get hungry around 12 and 5. When people are able to buy food (lunch breaks and end of work day) will also limit such fluctuations. Maybe a sine wave will form but there probably isn't enough people with the ability or forsight to try and game the system.