well, flogging is reserved usually for rapists, molesters or vandals. if you spit in the street, that's a fine, although i've seen many people do it.
it is not illegal to walk down the street eating.
we have a low crime rate, but that hasn't stopped the police from putting out a LOW CRIME MEANS NO CRIME advert.
littering is a crime, because quite frankly it's not right. punishments are fine and corrective work order, which means you wear a yellow jersey and clean up a public area for a few hours.
as far as i know it is not an offence to not stand by a vending machine to eat.
clean depends on where you go. generally the touristy areas = clean. in residential areas there's a 'cleanest estate' competition which i think is paying off well.
compulsory curfews were only enforced in the 1960s due to rioting, there aren't any now so there is no need for any. however, certain people during the sars outbreak were ordered to quarantine themselves at home for 10 days to prevent it's spread.