Japan Travel Fixes
Is eating while walking considered bad manners?
On streets known for street-food snacking (like some Osaka shopping arcades), eating right in front of the stall is the norm. Elsewhere, eating while walking is generally seen as poor manners and tends to create litter, so it's best avoided.
Some areas (including parts of Kyoto) ban eating while walking by local ordinance, so follow posted signage where it exists.
Most stalls provide a spot to eat standing nearby along with a trash bin — finishing your food there before moving on is the safe approach.