Answer:
1. We need a lawyer because they can defend us in front of the Jury if we do something bad.
2. We don't have to buy from those kinds of people and those kinds of stores, but it is often thought that they have good quality and everything which includes that.
3. Well, if you don't pay your electricity bill, they're going to turn the electricity off. If you don't pay your water bill your water will get turned off. And if you don't pay your loans your house might be put to sale because you have to give money in one way or another, and if you don't have any money you might end up in prison.
4. Because it's safer to keep your money in a bank instead of your pocket. They can take your materialistic things, but cannot take the money from the bank unless they know your password (which you should only know and should never write anywhere).
5. As I said in the previous one, someone may come across your password which can result in all your money being taken unless you block your bank account and report it to the police. There are many different scenarios about this situation and the procedure is long (I think) trying to get a new card with a bank account.
Those are the answers to your questions. Have a good day :-)
