AWS is full of dark patterns. You can sign up for the so-called "free" tier and then too easily, unwittingly enable something that suddenly charges you hundreds of dollars before you know it (by getting a bill at the end of the month), even if you're not doing anything with the service except looking around. AWS doesn't give any warning to free tier members that a configuration change is going to cost you, and their terms are also very confusing. For example, PostgreSQL is advertised as free, but "Aurora PostgreSQL" is quite costly.