The Sani music festival in northern Greece is celebrating its 30th anniversary this month. In the balmy night air, big crowds turned out to hear Irish rock star Bob Geldof and his band the Bobkatz strum through some Boomtown Rats classic hits. Geldof is famous for his fundraising activities fighting famine, and he used his appearance to warn about the impact of the war in Ukraine on world food supplies. “Putin is using food as a weapon,” he told Euronews. “Millions of people, people who have never heard of Ukraine, people who have never heard of Putin, will die because of what he is doing.” “H…