Those weird Persian and Arab cultures

"But when he was preparing to deliver his speech, a group of around 100 protesters, described by the news agency as “Ahmadinejad fans,” started throwing shoes and small stones used by Shiite worshipers when they pray, actions that are regarded as gravely insulting."  Gravely insulting? Those Iranians and Arabs are just too weird.  They consider pelting of shoes and stones at people to be insulting? How weird is that?  I pelt my neighbors here in California with stones and shoes regularly and no one has ever complained.