In Brazil, arriving half an hour late is one of the customs that has become common and tolerable. In Germany, keeping someone waiting is one of the rudest things you can do. The ideal is to arrive even a few minutes before.
In Brazil it is common to tip the waiters for the professional service in order to encourage and reward them for the service.
Although it is a pleasant custom here, in Asian countries such as Japan and South Korea, tipping the person serving you can be perceived as an offense. In this sense, they usually refuse the money and may even return it to you if you leave a few change on the table, as usual.
Despite being a nice and innocent gesture in Brazil, in countries like the Middle East, this sign is a offensive gesture and is equivalent to showing the middle finger over here.
It is very common to add sauces and seasonings to enhance our meals, but for many this is an affront. In Spain and Japan, for example, if you do that it can cause discomfort. In Italy, by the way, putting ketchup on pizza is almost an offense!
It is customary to eat anywhere to save time in our routine in Brazil, but this can be a problem in other countries. Eating in the street, on the bus and in other public places that do not serve food, it is considered rude behavior in Rwanda. Even eating an ice cream can be frowned upon.
In Singapore, for example, in addition to being impolite to do so, you are subject to paying a equivalent fine of R$ 1 thousand, in case you spit it out on the street. Even in this country the import of chewing gum has been banned for a long time