It's not illegal to waste food in Japan, although it's considered rude and poor etiquette to waste food in Japan, and some restaurants in Japan may also charge you a fee for over ordering at some of the "all you can eat" food establishments if you don't all.
While it's not illegal to waste food in Japan, Japan does have a law that promotes food loss and waste reduction through public awareness campaigns, government initiatives and industry goals.
You can eat with your hands in Japan depending on the food although for some foods it can be considered rude to eat with your hands in Japan.
Eating foods like sushi in Japan with your hands is appropriate although eating most other foods with your hands is considered rude.
For eating everything else, other than sushi, chopsticks are the standard utensil for eating in Japan, but you can also use forks, spoons and knives when available, especially for dishes like pasta or steak or other traditional Western dishes.
Eating bread or fries is also okay with your hands but most other foods it's rude to eat with your hands in Japan.
You can eat with utensils or chopsticks using your left hand in Japan as it's perfectly acceptable to eat with your left hand in Japan, especially if you're left handed.
Historical superstition once existed about eating with your left hand in Japan, but modern Japan now recognizes left handedness as a natural trait and it's not considered rude to eat with your left hand in Japan.
Many Japanese people and Japanese restaurants understand that you may need to eat with your left hand and accept it.
Japanese etiquette also focuses more on respectful behavior, like not placing your elbows on the table or doing "inu gui" which is eating like a dog by lowering your face to the bowl.
Things you should not do as a tourist in Japan are eat or drink while walking, avoid public noise and also don't wear any overpowered cologne or perfume and also separate trash, avoid blowing your nose in public and show respect for private areas and also cultural practices such as photography rules and personal space.
When in Japan as a tourist, you should avoid loud conversations and loud phone calls and keep your voice down when on public transport and when in restaurants and on the street and don't take or have phone calls when on the trains in Japan.
Finish any food or drink in the store or a designated area before moving as the lack of public trash cans in Japan is a factor for this.
It is also rude to refuse food in Japan, unless you've already been given plenty of food to eat.
In Japan refusing food is considered rude when it's offered by a friend, a host or during a business meeting as it can be seen as you rejecting hospitality and so it's more polite to accept the food, even if you don't plan to eat it all.
Or you can politely decline with phrases like "Thank you, I'm full," instead of just a direct no.
If you can't eat something because you have allergies, are full or dislike it, it's often better to accept the food and not eat it and you can also just give a gentle refusal.
Leaving a little food on your plate, especially rice, can also signal that you're satisfied and don't want more, as opposed to finishing everything, which could be interpreted as asking for a second helping.
Refusing food or drink that is offered by a business associate can be particularly rude and can negatively affect any business dealings in Japan.
It's considered rude while eating in Japan to walk while eating, stick the chopsticks upright in rice, make loud chewing noises or burping when eating and it's also rude to pass food from chopstick to chopstick in Japan while eating.
Other rude behaviors while eating in Japan are resting your chopsticks on the bowl, stabbing your food with chopsticks as well as blowing your nose at the table.
When in Japan do not stick your chopsticks upright in your rice as it's a funeral custom and do not pass your food directly from one pair of chopsticks to another, which is also associated with funerals.
While you can drink coffee or other beverages on the street in Japan it's also considered rude to walk and drink coffee or other beverages in Japan.
It's not illegal to drink coffee or other beverages while walking in Japan, but it's simply seen as rude so it's best to avoid it.
The custom in Japan when drinking coffee and other beverages, is to finish the coffee or other drinks when standing near where you purchased the coffee or other beverage.
Then you can dispose of the empty cup or trash where you're located.
The main reason for not drinking your coffee or other beverage while walking in Japan is because of a lack of public trash cans, which means that you would have to carry your trash with you.
Although I've seen some people dispose of their cups and cans and other trash around trees etc, when I visited Japan but it's not what you should do.
Drink your coffee or beverage near the vending machine or convenience store where you bought it and then dispose of the trash properly and use the bins that are provided at the store or the vending machine to dispose of the trash.