Is that considered a legal contract?

Well, it is either a legal contract or an illegal contract that you will have to fight about in court. Rich people who can afford attorneys generally do not buy timeshares. No lawyer would ever suggest that any client buy a timeshare. So, in other words, anyone with access to a family lawyer would never buy a timeshare.

If it's illegal, you can simply not pay, and THEY have to fight it in court.

You can also do this if it's legal, but the court might not be favourable to you.

>> you can simply not pay, and THEY have to fight it in court.

Yes. They will sue you in court. Then, when you don't answer and/or attempt to represent yourself, you will end up paying the default judgement. A judge isn't going to nullify a contract on their own. You have to explain to them why the contract is illegal, which is not as easy as everyone seems to think. That is what lawyers are paid to do.

That’s why many countries have government “watchdogs” you can report illegal contracts to, who will investigate it and potentially sue the company if they believe its a scam or somehow against consumer rights.