I’m surprised she agreed to do it, really. After all, she was always incredibly thin thanks to an eating disorder developed during the German occupation of her home country of Holland. In the Dutch Famine that followed in the winter of 1944, the Germans blocked the resupply routes of the Netherlands’ already-limited food and fuel supplies as retaliation for railway strikes that were held to hinder German occupation. People starved and froze to death in the streets; Hepburn and many others resorted to making flour out of tulip bulbs to bake cakes and biscuits
When the country was liberated, Hepburn said in an interview that she fell ill from putting too much sugar in her oatmeal and eating an entire can of condensed milk. Hepburn’s wartime experiences then sparked her devotion to UNICEF.
So she wasn’t really that into eating shitty chocolate on a bus, not that Mars or whoever is behind that ad gives a fuck.