While Traveling, the Royals aren't Allowed to Eat...
Shellfish. The same goes for raw meat and tap water, due to the fact that the quality of these aliments can't be verified for meeting royal standards and therefore could pose a high risk of food poisoning. This would obviously be problematic not only for their health but also for their extremely busy schedules. Will and Kate broke protocol, however, when they accepted to eat raw geoduck (a type of clam native to the west coast of North America) in 2016 during a tour of Canada.