I would like to ask a question I hope you can answer ... Is it legal that when you pay the bill with your credit card in a restaurant the waiters will charge your tip at their discretion without your consent ...? .... when you already leave

Good afternoon Angelica. I was on holiday. I am from Australia and it is not a custom to tip here. So it is all new to me too. I think what they do is to give you the bill when you request it and you put the tip on top of the bill. And you choose the amount. Depending on what you think the it should be and how they waiter performed. If you think they deserved 5% or 10% or 15%. It's up to you. Usually they are pretty cool with people from over seas. And understand that it is not a custom in your country. Hope this helped. Enjoy your trip.

Some restaurants have an 18 - 20% mandatory tip automatic gratuity included in the bill for large parties (10 or more guests)

If you pay the tip on your credit card, they will charge you after theyve charged you for your food. When paying the tip on your card always write clearly on the signed reciept how much you are tipping .